K18 Biomimetic Hairscience Leave-in Molecular Repair Hair Mask 50ml

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79.10€

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Image 1 - A split image shows a smiling woman with frizzy brown curly hair on the left labeled before, and the same woman with more defined brown curly hair on the right labeled after, with K18 hair product bottles and jars displayed at the bottom right alongside the text detox, mask, conditioner, and oil. Image 10 - A K18 Leave-In Molecular Repair Hair Mask bottle is shown on a pink and purple background with white spheres, next to text that calculates: healthy hair math 50 pumps (per 50ml K18 mask) ÷ 2 pumps (per weekly wash) = $3 a week Your healthiest hair costs less than your coffee, thanks to our highly concentrated molecular repair mask. The bottle label says K18 BIOMIMETIC HAIRSCIENCE leave-in molecular repair hair mask masque capillaire sans rinçage à réparation moléculaire 50 ml / 1.7 fl oz liq. Image 2 - A split image shows a smiling woman with curly red hair, before and after using a product, with the left side showing frizzy hair and the right side showing more defined curls, next to a bottle labeled K18 BIOMIMETIC HAIRSCIENCE, all with visible text before, after, and K18 mask. Image 3 - A before and after image displays the back of a persons long hair, showing dry, frizzy hair on the left labeled before, and smooth, shiny hair on the right labeled after, with K18 PEPTIDE PREP detox shampoo, K18 LEAVE-IN MOLECULAR REPAIR HAIR MASK, and K18 MOLECULAR REPAIR HAIR OIL products positioned below, and the text detox, mask, and oil at the bottom. Image 4 - A white K18 leave-in molecular repair hair mask bottle with a pump dispenser against a pink and orange gradient background, along with the text: K18 BIOMIMETIC HAIRSCIENCE™ leave-in molecular repair hair mask masque capillaire sans rinçage à réparation moléculaire 50 ml / 1.7 fl oz liq, patented K18PEPTIDE™ reverses damage from bleach, color, chemical services + heat*, highly concentrated formula, for all hair types, works in 4 minutes, easy leave-in, no rinse needed, vegan + cruelty-free, BEST OF BEAUTY allure THE BEAUTY EXPERT AWARD WINNER 2022, *k18hair.com/disclaimers. Image 5 - A circular diagram on a pink and orange gradient background illustrates the K18 hair routine, asking where does K18 fit into your routine?, with steps shampoo (skip conditioner), towel dry, K18, wait 4 minutes, and everything else which includes salt spray, mousse, hairspray, rewet hair, plop, air dry or oil, straighten, blow-dry or diffuse, gel or curl cream, leave-in conditioner, heat protectant, brush or comb hair. Image 6 - An illustration depicts the layers of a hair strand from the innermost polypeptide chains to the outermost cuticle, with labels for intermediate filament, microfibril, and cortical cells, and includes the text: where K18 molecular repair works, polypeptide chains this is where the K18PEPTIDE™ works to reconnect broken chains, renewing hair strength + elasticity, and cuticle this is the outside layer where shampoos + conditioners work. Image 7 - The image displays two white K18 Biomimetic Hairscience Leave-In Molecular Repair Hair Mask bottles, one 50ml and one 15ml mini size, on a pink and orange background, with visible text stating less is more, start with 1 pump, add more as needed (average use is 2 pumps), start with 3 pumps, add more as needed (average use is 6 pumps). Image 8 - Image displaying frequently asked questions about K18 hair products on a pink to orange gradient background. Text reads: maximize your repair why detox? K18 detox shampoo removes product buildup, oil, and metals and minerals from hair. Clearing buildup ensures maximum penetration of the K18PEPTIDE™. why skip conditioner? Conditioner can block the K18PEPTIDE™ from penetrating effectively. why wait 4 minutes? Wait 4 minutes before applying additional products to allow the K18PEPTIDE™ to provide maximum reparative benefits and to reach the innermost layers of your hair. how often should I use the K18 mask? Use for 4-6 consecutive washes then every other wash or as needed. do I need to warm between my hands to activate? No, you don’t need to do anything to activate the product. You can work between your hands to help with even distribution. Image 9 - The image shows the K18 repair routine displayed against a pink and orange background, featuring three numbered hair products: (1) detox shampoo, eliminate buildup, a K18 BIOMIMETIC HAIRSCIENCE PEPTIDE PREP detox shampoo, shampooing détoxifiant, 250 ml / 8.5 fl oz liq bottle; (2) mask, reverse damage, a K18 BIOMIMETIC HAIRSCIENCE leave-in molecular repair hair mask, masque capillaire sans rinçage à réparation moléculaire, 50 ml / 1.7 fl oz liq bottle; and (3) oil, fight frizz, a K18 BIOMIMETIC HAIRSCIENCE molecular repair hair oil, huile capillaire de réparation moléculaire, 30 ml / 1 fl oz liq dropper bottle.

K18 supplies you with the tools you need to express your identity, try new trends and have fun with your mane, without sacrificing the softness, strength and vitality of your hair. By understanding the biology of your locks, the brand gets right to the root of hair damage. Can't think of a way to restore your hair's elasticity and bounce? Cue: the K18 Leave-In Molecular Repair Hair Mask (50ml).

Repair and revive damaged hair with the K18 Leave-In Molecular Repair Mask (50ml), a science-backed treatment designed to strengthen strands for healthier-looking tresses.

Powered by K18Peptide Technology, this mask penetrates deep into hair to reconnect broken keratin chains, improving elasticity and softness. The leave-in formula is designed to work in minutes to protect and nurture hair compromised by bleach, dyeing, heat and chemicals. The result? Stronger, softer, smoother and bouncier locks full of life.

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.

For the latest information, it is recommended to review the ingredient list printed on the packaging of the product prior to usage or consumption.

Shampoo and rinse. Do not use conditioner, towel dry hair thoroughly, apply Leave-In Molecular Repair Mask and wait four minutes. Do not rinse out. After four minutes, apply styling products if desired and dry/style as usual.

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Customer Reviews

Top Customer Reviews

Thanks for sharing your thoughts! Please remember that results will vary from person to person. We're proud to say that all customer reviews are independent, authentic and do not represent the views of Cult Beauty or The Hut Group.

Top product!

Worth the hype, once you get how to use it it will become a must in your routine!your hair will look healthy, non frizzy…i love it

2026-07-03 by Maria Verified Purchase

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Give me my money back 🫠

To be honest, I still don't get this product! I followed the instructions perfectly, but my hair ended up looking matte and feeling awful to the touch, almost like it had a soapy residue. It was a total nightmare! I have dry, porous, bleached hair, so technically this should have worked wonders for me, but the result was just completely off.

2026-06-27 by Milagros Verified Purchase

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Expensive but amazing

I hope this stuff was cheaper, I have long dyed hair, and I need to use around 4 full pumps to cover most of my hair. It really does something, my hair feels more elastic and less dry. I shampoo, leave it for 5 min, and then apply a hair mask.

2026-06-26 by Adrig Verified Purchase

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The best

I don’t dye my hair but I noticed less breakage since using it. Wow!

2026-06-22 by E.A.

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life saver

so glad i bought it, i use it 1 time per week now that i have bleach hair. it creates a film that protect the hair and it’s also perfect for fine and way hair it doesn’t wait anything

2026-06-20 by eryngiu Verified Purchase

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I like it, but expensive

I have used it for a while and I like it but it’s very expensive

2026-06-06 by Delancy Verified Purchase

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best of the best

I love it! After just a few uses, my hair feels noticeably stronger, softer, and much healthier, with far less breakage. It’s one of the few products that has made a real difference to the condition of my hair, and I’ll definitely keep repurchasing it

2026-06-04 by Malin

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So good

It is so good and worth it a bit tricky to use and expensive

2026-06-03 by Paola

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Game changer

Definitely saved my dry damaged ends. Worth every penny.

2026-05-31 by Maggie Verified Purchase

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Love it!

Barely split ends since using. My hair is shiny and healthy

2026-05-29 by E.A.

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