K18 Biomimetic Hairscience
Leave-In Molecular Repair Hair Mask
Highly rated by customers for:
$107.50or 4 payments of $26.88 with 
or 
Size: 1.7 fl oz/50 mL
Standard size
Mini size
Highlights
Clean at Sephora
About the Product
Item 2927374
Only at Sephora
What it is: A leave-in treatment mask for all hair types that clinically targets damage in four minutes, restoring strength, softness, smoothness, and bounce to hair.
Hair Texture: Straight, Wavy, Curly, and Coily
Hair Type: Fine, Medium, and Thick
Hair Concerns:
- Color Safe
- Damage, Split Ends, and Breakage
Key Benefits:
- Restores strength, softness, smoothness, and bounce
- Cares for damaged hair
- Easy leave-in formula delivers lasting results
Highlighted Ingredients:
- K18Peptide: Cares for damage from bleach, color, chemical services, and heat.
Ingredient Callouts: This product is vegan and cruelty-free.
What Else You Need to Know: This mask is powered by the patented K18Peptide, which is just the right size and molecular structure to reach the innermost layers of hair and re-connect broken keratin chains responsible for hair's strength and elasticity.
Fragrance Description: K18's signature light-floral scent features notes of jasmine and peony.
Clinical Results: In a clinical study on hair that was bleached 8 times, after 2 uses:
- Biotech-powered K18Peptide restored damaged hair by up to 82%
Clean at Sephora
Clean at Sephora is our commitment to offering effective products without certain ingredients, such as parabens, sulfates, phthalates, and mineral oils. Learn more here.
Hair Texture: Straight, Wavy, Curly, and Coily
Hair Type: Fine, Medium, and Thick
Hair Concerns:
- Color Safe
- Damage, Split Ends, and Breakage
Key Benefits:
- Restores strength, softness, smoothness, and bounce
- Cares for damaged hair
- Easy leave-in formula delivers lasting results
Highlighted Ingredients:
- K18Peptide: Cares for damage from bleach, color, chemical services, and heat.
Ingredient Callouts: This product is vegan and cruelty-free.
What Else You Need to Know: This mask is powered by the patented K18Peptide, which is just the right size and molecular structure to reach the innermost layers of hair and re-connect broken keratin chains responsible for hair's strength and elasticity.
Fragrance Description: K18's signature light-floral scent features notes of jasmine and peony.
Clinical Results: In a clinical study on hair that was bleached 8 times, after 2 uses:
- Biotech-powered K18Peptide restored damaged hair by up to 82%
Clean at Sephora
Clean at Sephora is our commitment to offering effective products without certain ingredients, such as parabens, sulfates, phthalates, and mineral oils. Learn more here.
-K18Peptide: Cares for damage from bleach, color, chemical services, and heat.
Water (Aqua) (Eau), Alcohol Denat., Propylene Glycol, Cetearyl Alcohol, Dicaprylyl Ether, Cetyl Esters, Behentrimonium Chloride, Polysorbate 20, sh-Oligopeptide-78 (K18Peptide), Hydrolyzed Wheat Protein, Hydrolyzed Wheat Starch, Isopropyl Alcohol, Tocopherol, Phenoxyethanol, Potassium Sorbate, Citric Acid, Fragrance (Parfum), Geraniol, Linalool, Hexyl Cinnamal, Benzyl Alcohol.
The list of ingredients is subject to change. Please consult the packaging of the product purchased.
Water (Aqua) (Eau), Alcohol Denat., Propylene Glycol, Cetearyl Alcohol, Dicaprylyl Ether, Cetyl Esters, Behentrimonium Chloride, Polysorbate 20, sh-Oligopeptide-78 (K18Peptide), Hydrolyzed Wheat Protein, Hydrolyzed Wheat Starch, Isopropyl Alcohol, Tocopherol, Phenoxyethanol, Potassium Sorbate, Citric Acid, Fragrance (Parfum), Geraniol, Linalool, Hexyl Cinnamal, Benzyl Alcohol.
The list of ingredients is subject to change. Please consult the packaging of the product purchased.
Suggested Usage:
-When in the shower, shampoo but don’t condition.
-Once out of the shower, gently towel-dry your hair until damp.
-Begin with one dime-size amount of K18 Mask.
-Only add more as needed—this is a highly concentrated formula, so you’ll need much less than traditional masks. The average use is 2 mL/two dime-size amounts.
-Work evenly into hair from ends to roots.
-Let sit for four minutes to activate.
-Don’t rinse out.
-Style as usual after the four minutes are up. It’s fine to add heat protectant or styling product now.
-Use for the first four to six washes, then swap to maintenance mode and use as needed.
-When in the shower, shampoo but don’t condition.
-Once out of the shower, gently towel-dry your hair until damp.
-Begin with one dime-size amount of K18 Mask.
-Only add more as needed—this is a highly concentrated formula, so you’ll need much less than traditional masks. The average use is 2 mL/two dime-size amounts.
-Work evenly into hair from ends to roots.
-Let sit for four minutes to activate.
-Don’t rinse out.
-Style as usual after the four minutes are up. It’s fine to add heat protectant or styling product now.
-Use for the first four to six washes, then swap to maintenance mode and use as needed.
Questions & Answers (0)
Meet K18 | We’re the biotech breakthrough that’s rewriting the rules on hair care. After 10 years of complex bioscience research, we unlocked our patented K18Peptide that reverses hair damage in four minutes. Born in the salon, stylists, colorists, and hair expressors of all generations are liberating self-expression without having to worry about damage. Our leave-in molecular repair hair mask works with the biology of your hair to strengthen from the inside out.