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Peptide mask · #22 hair Generated scene, not a product photo
K18 · Hair · Treatments and masks

K18 Leave-In Molecular Repair Hair Mask

A peptide leave-in: four minutes on damp, shampooed hair with no rinse, according to the maker. Alcohol denat is the second ingredient, and owners split hard over the $75 MSRP.

50 mlTreatmentsh-Oligopeptide-78Hydrolyzed wheat proteinScented
$75 MSRPAmazon price not shown
Check price on Amazon →

Amazon link · we earn a commission if you buy · $75 MSRP · Amazon price not shown · verified Nov 1, 2026. More stores appear here as each affiliate program approves the site.

Buy it if

  • Your hair is badly bleached and you have tried the cheaper options
  • You will follow the routine; owners say technique decides it
  • You want a leave-in that takes little product

Walk past if

  • Your hair is healthy; this is a lot to spend on nothing
  • Your ends run dry; some owners got drier, frizzier hair
  • You mind a sticky feel; owners compare it to glue

What's in it

The ingredients that do the work, from the maker’s label.

sh-Oligopeptide-78Hydrolyzed wheat proteincontains alcohol

Sulfate-free →

Worth knowing: contains fragrance, contains alcohol.

Full ingredient list, from the maker

Water (Aqua) (Eau), Alcohol Denat., Propylene Glycol, Cetearyl Alcohol, Dicaprylyl Ether, Cetyl Esters, Behentrimonium Chloride, Polysorbate 20, sh- Oligopeptide-78, Hydrolyzed Wheat Protein, Hydrolyzed Wheat Starch, Isopropyl Alcohol, Tocopherol, Phenoxyethanol, Potassium Sorbate, Citric Acid, Fragrance (Parfum), Geraniol, Linalool, Hexyl Cinnamal, Benzyl Alcohol, Amyl Salicylate, Benzaldehyde

Known issue

Owners report a sticky, glue-like feel and dry, frizzy ends, and others see nothing for the price after several washes.Walmart and MakeupAlley reviews

What owners say

Filled by the research pass: two or three owner reports from named venues, each linked, each with the date it was read.

If it's not right

SheaMoisture Manuka Honey & Mafura Oil Intensive Hydration MasqueNo maker list price for this sizeA thick deep conditioner of coconut oil, shea and mafura butter for dry curls. The maker says five minutes, or up to thirty under a cap with heat. Fine hair tends to get a film.Nizoral Anti-Dandruff ShampooNo maker list price for this sizeKetoconazole 1%, labeled by the maker to control flaking, scaling and itching associated with dandruff. The carton says to use it every 3 to 4 days for up to 8 weeks, then only as needed.

Sources

  1. Maker page: ingredient list, 50 mL list price, four-minute directions and the instruction not to rinse.
  2. Walmart reviews, 1.7 oz, 4.0 from 71: a glue-like feel, dry or frizzy hair, and repeated reports of suspect bottles from marketplace sellers.
  3. MakeupAlley reviews, about 3.5 of 5 from 24: drier ends with frequent use, overpriced for some, and no change after six washes for one. (read from a search excerpt)

Ingredient lists from the maker's label, not our measurements.