37% stronger hair against breakage
A brand-run study. We report it as stated and do not repeat the number as fact.
—
Stated by brand
Only the brand’s testing shows this.
Davines
HEART OF GLASS Instant Bonding Glow
Finisher / Serum, light-reflecting
- Finisher
- serum
- Sulfate-free
- Silicone-free
- Moisture-rich
- Cruelty-free · brand states
Size10.14 fl oz (300 ml)
Priceabout $54 Good valuecommonly seen · 10.14 oz
Price / oz$5.33/ozat 10.14 oz
Where to buy6 stores · $48.00–54.00
Add it to your products. We’ll tell you if it’s ever recalled.
Scent:
Notes: citrus, florals, green notes, spice.
“Fresh citrus and spice leading to crisp green notes and soft florals” (Brand page)
Manufacturer page: us.davines.com
Personal fit
Is this right for you?
Complete the consultation to see how well this product fits your hair and your goals. With 6,000+ products in our library, we can match you to the right ones.
- About 20 minutes, and your answers save as you go.
- Every product matched against your hair across the 23 factors we check.
- A personalized routine built around your schedule, styling habits, and local weather.
- Find products that do the same job at a lower cost.
- Your goals, scalp, damage history, water, budget, and scent preferences all shape your plan.
$49 with 60 days of follow-up questions and plan updates
$99 with 12 months. Pay once; the year renews only if you choose.
Factor
Your profile
Fit
Best for hair types
All types
Not in your profile
Moisture level
High
Not in your profile
Shine system
Moderate
Not in your profile
Slip / detangling
High
Not in your profile
Weight on hair
Medium
Not in your profile
Fragrance
Prominent
Not in your profile
Protein
Minor
Not in your profile
Silicone / wax buildup
None
Not in your profile
Clarifying wash needed
Low
Not in your profile
Scent
Citrus · Amber & spiceStrength not recorded
Not in your profile
Show all 23 factors we check
The rest of what your plan weighs on this product.
Parabens / preservatives
None of these listed
Not in your profile
Essential oils
None listed
Not in your profile
Fast-drying alcohol
Moderate
Not in your profile
Vegan / cruelty-free
Cruelty-free · brand states
Not in your profile
Animal-derived ingredients
Not yet verified
Not in your profile
Aerosol can
Pump or tube
Not in your profile
Needs heat to set
Not determined
Not in your profile
Heavy humectants
Heavy
Not in your profile
Hard-water defence
None
Not in your profile
UV filter
None listed
Not in your profile
Ingredient list
29 ingredientsAbout average
Not in your profile
Price tier
Prestige
Not in your profile
Where to buy it
Brand websiteOne channel
Not in your profile
The consultation builds your hair profile, checks every factor in this table against it, and tells you where this product fits or what to use instead.
Start your consultation$49 once, with 60 days of follow-up questions and plan updates. Nothing renews, and you never have to buy a product.
Your avoid-list
Priced with its peers
$5.33/oz at 10.14 oz, less than 69% of the 136 serums , which mostly run $3.94–14.80/oz.
Great for
Maximum slipfor hair that tangles the moment it is wet
Dry, thirsty hairhumectants and emollients both sit up front
Silicone-free routinesno silicones appear in the list
Stretching wash daysnothing here needs a detergent to remove
Dull-looking haira recognised shine system is present
Aerosol avoidancea pump or tube, not a pressurised can
Maybe skip if
this product has a scent
Very dry or damaged hairit contains fast-drying alcohol
Dry or very humid airwhere heavy humectants work against you
Tight budgetsit sits in the upper price tiers
Picking it up locallywe’ve only seen it sold in one channel
What the formula actually does
Read from the label, not the marketing
Each row says where it comes from: F means we derived it from this product’s own ingredient list, S means it is a claim the brand makes that the formula neither confirms nor contradicts.
Shine system
Single oil
Light esters or a volatile carrier: shine with little residue.
Weight on the hair
Medium
Middle of the range: noticeable on fine hair, light on coarse hair.
Oils and butters
Present, lower down
Oils are present, but low enough to be a finishing touch.
Needs detergent to remove
No
Nothing here needs a detergent wash to remove.
Fast-drying alcohol
Present
Contains fast-drying alcohol, which speeds drying but can leave hair feeling dry.
Fragrance
Prominent
Fragrance is in the first eight ingredients, so it makes up a larger share of the formula.
from the formula
stated by the brand
reported by reviewers
Scale: 1 dot low · 5 dots high, within this product type.
Ingredients that matter
The ingredients that change a decision
The workhorse ingredients, plus anything lower down that changes a decision. The chips name what an ingredient does. They are not safety scores, and no ingredient here is rated good or bad on its own.
| Ingredient | What it does | Why it matters | Chip |
|---|---|---|---|
| WaterAqua / Water / Eau | solvent | The base everything else is dissolved in | Neutral |
| Propylene Glycol | humectant | Pulls water into the hair | Moisturizes |
| Caprylic/Capric Triglyceride | light ester | Light slip without much weight | Shine |
| Glyceryl Stearate Se | emulsifier | Keeps oil and water mixed | Shine |
| Cetrimonium Chloride | conditioning agent | Conditions and softens so hair combs through | Detangles |
| Behentrimonium Chloride | conditioning agent | Conditions and softens so hair combs through | Detangles |
| FragranceParfum / Fragrance | fragrance | The scent | Fragrance |
| Glycerin | humectant | Adds a little water-binding | Moisturizes |
| Isopropyl Alcohol | drying alcohol | A small amount, for fast drying | Drying |
| Alpha-Isomethyl Ionone | fragrance | The scent | Fragrance |
| Linalool | fragrance | The scent | Fragrance |
| Coumarin | fragrance | The scent | Fragrance |
What the list leaves out, and what it carriesThe list carries no sulfates or silicones. Fragrance is on the label. Contains fast-drying alcohol.
Full ingredient list (29)
In the US, ingredients above 1% are listed from most to least. Below 1% they can appear in any order. Each note keeps three things apart: what the ingredient generally does, its role in this type of product, and what its position can tell you.
-
1
Water
· Aqua / Water / Eau
General function
The base of almost every rinse-off and cream hair product. It carries everything else and is normally the first ingredient on the label.
Leading ingredientListed in the first three ingredients, it is likely a structural part of this formula.
- solvent
-
2
Propylene Glycol
General function
A small humectant and solvent that keeps formulas stable and helps active ingredients spread.
Leading ingredientListed in the first three ingredients, it is likely a structural part of this formula.
PubChemMay suitFine or easily flattened hairLight and water-binding rather than oily, so it adds less weight than oils or butters do.
May suitVery dry or highly damaged hairA small water-binding solvent. It holds moisture and helps the rest of the formula spread evenly over the strand.
DependsClimate-sensitive or frizz-prone hairA humectant follows the air: it holds water in humid conditions and can give it up in very dry ones. Climate decides what it does more than the label does.
- humectant
- solvent
-
3
Caprylic/Capric Triglyceride
General function
A light, refined coconut-derived oil that spreads easily and does not go rancid. It gives slip without a heavy feel.
Leading ingredientListed in the first three ingredients, it is likely a structural part of this formula.
May suitFine or easily flattened hairA light emollient: it softens the surface with noticeably less weight than an oil or a butter.
May suitFrizz-prone, damaged, or high-friction hairSpreads thin and lowers friction between strands without the heaviness of a fixed oil.
- light ester
- emollient
-
4
Glyceryl Stearate Se
General function
A self-emulsifying version of glyceryl stearate that builds a cream on its own.
Supporting ingredientListed in positions 4–8, it likely makes a meaningful contribution alongside the formula's main ingredients.
PubChemMay suitFrizz-prone, damaged, or high-friction hairEmollients fill and smooth the surface of the strand, which lowers the friction that lifts the cuticle and reads as roughness.
- emulsifier
- emollient
-
5
Cetrimonium Chloride
General function
A quick-acting conditioning agent that reduces static and combing force. It also helps keep the formula stable.
Supporting ingredientListed in positions 4–8, it likely makes a meaningful contribution alongside the formula's main ingredients.
International Journal of Cosmetic ScienceMay suitFine or easily flattened hairThe C16 quat binds mostly by charge rather than by chain, so it deposits measurably less than the C22 ones. Less deposit is less conditioning and also less weight, which is usually the trade fine hair wants.
May suitFrizz-prone, damaged, or high-friction hairA cationic conditioning agent: it binds to the damaged, negatively charged parts of the cuticle and lowers combing friction there.
DependsBuild-up-sensitive routinesSubstantive by design. A routine with no detergent wash gives it nothing to leave with.
- conditioning agent
- cleanser
-
6
Behentrimonium Chloride
General function
A positively charged conditioning agent that binds to damaged, negatively charged spots on the hair. It is the main detangling ingredient in most rinse-out conditioners.
Supporting ingredientListed in positions 4–8, it likely makes a meaningful contribution alongside the formula's main ingredients.
International Journal of Cosmetic ScienceMay suitDry, coarse, or high-porosity hairElectrokinetic measurement puts the C22 quat ahead of the C16 ones for deposition: the longer chain adds van der Waals stabilisation on top of the charge binding. That extra deposit is what coarse hair usually needs to comb through.
May suitFrizz-prone, damaged, or high-friction hairA cationic conditioning agent: it binds to the damaged, negatively charged parts of the cuticle and lowers combing friction there.
DependsBuild-up-sensitive routinesSubstantive by design. A routine with no detergent wash gives it nothing to leave with.
- conditioning agent
- cleanser
- ▾Below about here, the order stops meaning much. These are usually used at 1% or less.
-
7
Fragrance
· Parfum / Fragrance
General function
An undisclosed blend of scent ingredients. Regulations let it stay unlisted, so a fragrance-free product is the only way to be certain what is not in it.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
May not suitFragrance-sensitive routinesDeclared fragrance. On a fragrance-sensitive routine this is the line that decides it, wherever it sits on the label.
- fragrance
- declared fragrance
-
8
Glycerin
General function
Glycerin, also called glycerol, attracts moisture and mixes completely with water.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
Scientific ReportsMay suitDry, coarse, or high-porosity hairHigh-porosity hair loses water fast; a humectant holds some of it in place for longer than the wash itself would.
May suitVery dry or highly damaged hairBinds water into the outer layers of the strand, and water is what makes dry hair flexible again rather than brittle.
DependsClimate-sensitive or frizz-prone hairWater moves both ways. Measured across concentrations, glycerin solutions give water up in some conditions and take it from the air in others. What it does for you depends on how much of it is there and on the air around it.
- humectant
-
9
Benzyl Alcohol
- preservative
- solvent
-
10
Cellulose
General function
Plant fibre used to thicken and give body to a formula.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
May suitCurls or waves needing flexible holdGums thicken and set soft, which gives definition that bends rather than a rigid cast.
- thickener
- gum
-
11
Polyester-37
General function
A polymer used to hold pigments and oils in a durable film.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
May suitClimate-sensitive or frizz-prone hairA set polymer film is a physical barrier to humidity, so a style keeps its shape longer in damp conditions.
May suitMaximum-hold stylingSynthetic film formers dry into a continuous film, which is what holds a shape against movement and against humid air.
DependsBuild-up-sensitive routinesSome acrylate copolymers rinse with water and some need a detergent; the label alone does not say which one a formula used.
- film former
- polymer
-
12
Isopropyl Alcohol
General function
A fast-evaporating alcohol used as a solvent and to speed drying. Well down the list it is a processing aid; near the top it can leave hair feeling dry.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
PubChemMay suitFine or easily flattened hairEvaporates on contact, which is how a spray sets almost instantly and leaves no weight behind it.
- drying alcohol
- solvent
-
13
Polyglyceryl-3 Polyricinoleate
- emulsifier
- emollient
-
14
Sorbitan Isostearate
General function
A fatty ester. Esters give slip and a smooth after-feel; lighter ones read dry and silky, heavier ones read rich.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
May suitFine or easily flattened hairA light emollient: it softens the surface with noticeably less weight than an oil or a butter.
May suitFrizz-prone, damaged, or high-friction hairSpreads thin and lowers friction between strands without the heaviness of a fixed oil.
- light ester
- emollient
-
15
Sclerotium Gum
General function
A fermented gum that thickens and gives a slippery, cushioned feel.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
May suitCurls or waves needing flexible holdA polysaccharide film stays softer than a synthetic one as it dries, which is what leaves a curl defined but still able to move.
May suitFrizz-prone, damaged, or high-friction hairA soft film binds neighbouring strands together, which is most of what helps flyaways lie down.
May not suitMaximum-hold stylingGum films stay soft. A style that needs firm fixation usually wants a synthetic polymer doing the holding.
- film former
- gum
- thickener
-
16
Sodium Benzoate
- preservative
-
17
Maleic Acid
General function
An acid used to adjust pH and, in bond-repair systems, as part of the reactive chemistry.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
DependsFrizz-prone, damaged, or high-friction hairpH adjusters are how a formula is brought to a chosen acidity, and an acidic formula keeps the cuticle lying flatter than an alkaline one. Which way this one moves the pH depends on the formula, and the finished pH is not on the label.
- pH adjuster
-
18
Caprylyl Glycol
General function
A gentle preservative helper that also holds a little moisture.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
PubChemMay suitVery dry or highly damaged hairHumectants bind water into the strand, and water — not oil — is what makes dry hair flexible instead of brittle.
DependsClimate-sensitive or frizz-prone hairA humectant follows the air: it holds water in humid conditions and can give it up in very dry ones. Climate decides what it does more than the label does.
- preservative
- humectant
- 19 Thioctamidoethyl Dimethylamine Maleate
-
20
Sodium Hydroxide
General function
A strong base used in trace amounts to raise pH; fully neutralised in the finished product.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
International Journal of TrichologyDependsFrizz-prone, damaged, or high-friction hairThe alkali half of a pH-adjusting pair, used in small amounts to bring a formula up to its target rather than to make it alkaline. Alkaline conditions raise the fibre's surface charge and lift the scales — but the finished pH is not on the label.
- pH adjuster
- 21 Sodium Surfactin
-
22
Ethylhexylglycerin
General function
A preservative booster that also adds a little softness. Almost always paired with phenoxyethanol.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
PubChemMay suitFrizz-prone, damaged, or high-friction hairEmollients fill and smooth the surface of the strand, which lowers the friction that lifts the cuticle and reads as roughness.
- preservative
- emollient
-
23
Alpha-Isomethyl Ionone
General function
A violet-like fragrance component named separately as a recognised allergen.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
PubChemMay not suitFragrance-sensitive routinesOne of the 26 scent components the EU requires to be named individually above a threshold. It is named because it is a known contact allergen, not because it is unusual.
- fragrance
- named fragrance allergen
-
24
Linalool
General function
A floral fragrance component listed separately as a recognised contact allergen.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
PubChemMay not suitFragrance-sensitive routinesOne of the 26 scent components the EU requires to be named individually above a threshold. It is named because it is a known contact allergen, not because it is unusual.
- fragrance
- named fragrance allergen
-
25
Coumarin
General function
A sweet, hay-like fragrance component listed separately as a recognised allergen.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
PubChemMay not suitFragrance-sensitive routinesOne of the 26 scent components the EU requires to be named individually above a threshold. It is named because it is a known contact allergen, not because it is unusual.
- fragrance
- named fragrance allergen
-
26
Hydrolyzed Adansonia Digitata Seed Extract
General function
A broken-down baobab seed extract, used for conditioning and strength claims.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
May suitFrizz-prone, damaged, or high-friction hairFilling surface gaps evens out the cuticle, which is part of what makes damaged hair comb and reflect light more like undamaged hair.
May suitVery dry or highly damaged hairHydrolysed fragments are small enough to sit in the gaps of a worn cuticle for a wash or two, temporarily restoring stiffness and cutting breakage in combing.
- botanical extract
- protein
- hydrolysed protein
-
27
Retinyl Palmitate
- vitamin
- antioxidant
-
28
Helianthus Annuus (Sunflower) Seed Oil
General function
A light, widely used oil that softens without much weight.
Estimated lower-concentration zoneIt appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
International Journal of TrichologyMay suitDry, coarse, or high-porosity hairCoats the surface and slows water leaving the strand, which is usually what coarse hair that dries out fast is missing.
May suitFrizz-prone, damaged, or high-friction hairA thin oil layer lowers friction between strands and flattens the raised cuticle that scatters light and catches on its neighbours.
- oil
- emollient
-
29
BHT
- antioxidant
What the whole list adds up to
- 6 emollients
- 4 solvents
- 4 fragrances
- 4 preservatives
- 3 humectants
- 3 named fragrance allergens
- 2 light esters
- 2 emulsifiers
- 2 conditioning agents
- 2 cleansers
- 2 thickeners
- 2 gums
- 2 film formers
- 2 pH adjusters
Ingredient list captured 2026-09-08. Formulas change, so check the package in your hand when an ingredient matters to you.
Price · 10.14 oz
Commonly seen
about $54
Good value under
$91
Usually a good value. Most stores sell it under the $91 line, and products that do this job typically go for about $108 at this size.
Show the price ladder
Where we’ve seen it6 listings · 6 stores
-
Face It! Spa and Wellness
$48.0010.14 oz · $4.73/ozSep 8Lowest per oz
-
Sephora
$54.0010.14 oz · $5.33/ozSep 8
-
Davines North America
$54.0010.14 oz · $5.33/ozSep 8
-
Nordstrom
$54.0010.14 oz · $5.33/ozSep 8
-
milk + honey
$54.0010.14 oz · $5.33/ozSep 8
-
Davines (us.davines.com)
$54.0010.14 oz · $5.33/ozSep 8
Sorted by price per ounce. Dated observations from our research, not live prices. Direct store pages, no affiliate links. We don’t sell this product.
How we work this out
- 10.14 oz is the size stores list most often; every comparison on this page is made at it. Other sizes are shown in the Sizes row and the store list.
- Commonly seen is the middle half of current prices for the 10.14 oz at recognised stores. We leave out the cheapest and most expensive quarters, so one sale or one overpriced listing can’t move it.
- Good value under $91 comes from the 8 products we score as doing the same job as this one. A quarter of them cost less than $8.98/oz; at 10.14 oz that is $91. Under that line you are paying less than most of them.
- About $108 is what those same products typically cost at this size: the midpoint of their prices per ounce, scaled to 10.14 oz.
Formula
9
Formula score
9 of 10
A complete formula at an ordinary price: mid-range per ounce among serums, with the working systems in place.
How the score is counted
- Costs less per ounce than 69% of the 136 serums we’ve priced
- Covers 5 of the 6 things a serum should do
- Prestige tier, sold at Brand website
- Prestige tier
- A shine systemThe silicone, oil, or ester that produces gloss.3 pts
- A weightless carrierDelivers the shine without leaving grease.2 pts
- Oils or butters in the working zoneSoftens the strand rather than just coating it.2 pts
- An antioxidantKeeps the oils in the bottle from going off.1 pt
- No drying alcohol in the first threeFast drying without leading on alcohol.1 pt
- Fragrance kept out of the top eightScent as a finishing touch, not a major share.1 pt
The formula score measures completeness for the job: a weighted share of the systems this product type is usually built around that we find in this list. It does not rate how well the product works or its quality, and it never compares across product types.
Does the same job
Formulas that do the same things (cleanse, condition, coat or hold) for less per ounce. Scent, texture and where you buy them can still differ.
Innersense Organic BeautyClosest function
Overnight Repair Serum
$10.50/oz $5.17/oz more
- Silicone-free
- Rinses clean
- Shine
- Function
- Also
DavinesLowest cost per oz
This is a Texturizing Serum
$5.92/oz $0.59/oz more
- Protein-free
- Silicone-free
- Rinses clean
- Function
- Also
VerbLighter feel
Density Peptide Hair Serum
$22.00/oz $16.67/oz more
- Lightweight
- Silicone-free
- Rinses clean
- Function
- Also
See more alternatives in the product library
These products do a similar job. We haven’t matched them to you. Find the one that fits your hair, routine and budget
Final decision
Should you buy it?
A solid pick for the hair it suitsBest user
People who want maximum slip, looking for real detangling slip and moisture that stays in
Biggest tradeoff
Worth skipping for anyone sensitive to fragrance, very dry or high-damage hair, or very dry or very humid climates
Best alternative if not
Nothing in our library matches it closely at a lower price.
We do not sell products or take placement fees. This page states what the formula and the prices show; the consultation is what matches it to a person.
Claims check
What the brand says, and what the formula shows
Claims are quoted from the brand. We mark a claim supported, partly supported or conflicting only when the ingredient list speaks to it. Everything else stays "stated by the brand". That isn’t a criticism: most claims can’t be checked from a label.
2
SupportedBacked by ingredients
0
Partly supportedSome supporting logic
2
Stated by brandNo clear evidence
0
Potential conflictFormula works against claim
6.4 times more luminous hair
The formula carries a recognised shine system — silicone, oil, or light ester.
- Caprylic/Capric Triglyceride
- Sorbitan Isostearate
Supported
Reflects light for visible shine.
Luminous colour up to 6 weeks
The formula carries a recognised shine system — silicone, oil, or light ester.
- Caprylic/Capric Triglyceride
- Sorbitan Isostearate
Supported
Reflects light for visible shine.
Preserves intensity of colour up to 83%
A brand-run study. We report it as stated and do not repeat the number as fact.
—
Stated by brand
Only the brand’s testing shows this.
How to read this
We look at the first 10–15 ingredients and what they do in a formula, not at the marketing. If the list doesn't speak to a claim, we don't assume.
More from Davines
How this page was made
- Everything above comes from our researched product record: identity, the ingredient list as printed, the brand's own claims, dated prices and review themes our researchers wrote in their own words. No part of this page is written by hand for one product.
- The value band is a fixed label over two stored numbers: this product’s cost per ounce as a percentile of every product of this type we have priced, each at the size it is most often sold in, and how many products we score as doing the same job cost at least a quarter less per ounce.
- Both scores out of ten are defined on this page. The formula score is completeness for the job, computed from a fixed per-format checklist shown beneath the gauge; the price score is cost per ounce against every product of this type we have priced.
- The "Is this right for you?" panel reads only your own consultation answers, and it applies exactly the filters our recommendation engine applies. It is computed when you load the page and is never stored on it.
- 5 sources consulted for this product (2 manufacturer or regulatory, 2 retailer, 1 editorial), last checked 2026-09-08.
- Ingredient references are linked for 13 of 21 product-aware annotations on this page. Fit notes are general formulation guidance. They aren’t a verdict on the finished product or on you.
- We haven’t tested this product in a lab, and we don’t physically test your hair. Formula readings come from the ingredient list. Claims about how it behaves are labelled as the brand's.
- Ingredient order tells you relative amount only above roughly 1%. Prices are what we saw on the dates shown and can change.
- Ingredient names link to our ingredient library, where each entry shows what it does, which product types use it, and where it usually sits on a label across everything we have researched.
- This is cosmetic information, not medical advice, and nothing here diagnoses or treats a health condition.
- Formula readings: derivation v23. Record last updated 2026-09-08.
