full-size leave-in molecular repair hair mask
4-minute leave-in treatment to reverse hair damage
A leave-in treatment mask that works on the molecular level to reverse hair damage in just 4 minutes*. The K18PEPTIDE™ is clinically proven to repair damage from bleach + color, chemical services and heat* – with immediate and lasting results to restore strength, softness, smoothness and bounce to hair.
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how does the k18 mask work?
The K18 mask works as a treatment to reverse damage in 4 minutes. It’s powered by our biomimetic K18PEPTIDE™ to seamlessly fit in and reconnect broken polypeptide chains at the molecular level. As a result, disulfide bonds are also reconnected for reinforced strength along the length + width of hair—offering comprehensive, lasting, and progressive repair.
what is the k18peptide™?
K18PEPTIDE™ is a biotech-developed peptide that mimics hair’s structure to reverse damage by reconnecting polypeptide chains and disulfide bonds broken during damage from bleach + color, chemical services, and heat*
*Disclaimers
why skip conditioner?
Conditioner leaves a film that blocks our peptide from penetrating effectively. Once the 4-minute wait time is up, feel free to use a conditioner, a leave-in, or any type of product.
i noticed there’s alcohol in the formula, isn’t that bad for you?
We like to keep our formulas minimal, only using the exact amount of ingredients needed to get the peptide where it needs to go. Here the alcohol serves as an agent to optimize the hair environment for the K18 mask to work on a deeper level. Our unique blend of 3 alcohols functions to open the hair cuticle so the K18PEPTIDE™ can penetrate the innermost layer of hair, reaching the broken polypeptide chains (keratin chains).
when should i expect to see results?
Most see results after 2-3 uses. The more damaged the hair, the more dramatic the results so it may vary depending on your hair type and level of damage.
Repair damage for hair like new* in 4 minutes.
1. Shampoo, do not condition. Towel-dry thoroughly.
2. Apply 1-3 pumps based on your length and density, starting at the ends and working up towards the roots.
3. Let sit for 4 minutes. Do not rinse out.
4. Comb, add styling product + style as usual. Use for 4-6 washes, then as needed.
*k18hair.com/disclaimers
See how K18 unlocks our community's expression
- Effectiveness
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- Repair
- Appearance
- Value
- Hazzel J.Verified BuyerReviewingFull-Size Leave-In Molecular Repair Hair Mask 50mLI recommend this productAge 18 - 24Hair Concern Chemical damage, Color-care, Frizz, Dryness, Split-EndsHair Type Thick/CoarseMy Results Less Frizz, Bouncy Hair, Visible Difference, Stronger Hair, Smoother HairRated 5 out of 5 stars2 hours agoAmazing for bleached hair
I absolutely love this product! My hairdresser recommended it to me, and I’m so glad I tried it. My hair is bleached and has been through a lot of processing, and K18 is honestly the only product I’ve tried that has made a noticeable difference. My hair feels so much healthier, softer, and more manageable after using it. A little goes a long way, too. Definitely worth it for damaged or bleached hair. I’ll absolutely keep using this! ❤️
KK18Hair1 hour agoWe're so thrilled your hairdresser recommended us! 💕 We love hearing that the Molecular Repair Mask is making such a noticeable difference for your bleached hair. Thank you for the love! ✨
- Henry M. C.Verified BuyerReviewingJumbo Leave-In Molecular Repair Hair Mask 100mLI recommend this productAge 65+Hair Concern Chemical damage, Dryness, Frizz, Heat damageHair Type Fine/Thin, Grey Hair, Curly/CoilyMy Results Less Frizz, Bouncy Hair, Visible Difference, Stronger Hair, Less BreakageRated 5 out of 5 starsYesterdayK-18 and what ever else you recommend please!
This item works for me.
KK18HairYesterdayThank you so much for your review, Henry! We're thrilled to hear the Jumbo Leave-In Molecular Repair Hair Mask is working great for you. We appreciate you being part of the K18 community! 🤍
- Lorraine C.Verified BuyerReviewingFull-Size Leave-In Molecular Repair Hair Mask 50mLI recommend this productAge 55 - 64Hair Concern Chemical damage, Fragile/brittle hair, Dryness, Split-EndsHair Type Fine/Thin, Straight/WavyMy Results Less Frizz, Stronger Hair, Less Breakage, Visible DifferenceRated 5 out of 5 starsYesterdaysaved my hair
Never thought is was true until now...this works
KK18HairYesterdayThank you so much for sharing, Lorraine! 🤍 We're thrilled to hear the Molecular Repair Hair Mask has made such a positive difference for your hair. Thank you for being part of the K18 community!
- Amera B.Verified BuyerReviewingJumbo Leave-In Molecular Repair Hair Mask 100mLI recommend this productAge 55 - 64Hair Concern FrizzHair Type Curly/CoilyMy Results Less Breakage, Soft Touchable Hair, Visible DifferenceRated 5 out of 5 stars2 days agoLove it
This has made quite a difference in my hair quality. I have been using it for a year now.
KK18Hair2 days agoThank you so much for your wonderful review! We're thrilled to hear that the Jumbo Leave-In Molecular Repair Hair Mask has made such a positive difference in your hair over the past year. We truly appreciate you being part of the K18 community! 🤍
- Amber H.Verified BuyerReviewingJumbo Leave-In Molecular Repair Hair Mask 100mLI recommend this productAge 55 - 64Hair Concern Chemical damage, Color-care, Fragile/brittle hairHair Type Medium DensityMy Results Less Frizz, Bouncy Hair, Visible Difference, Less Breakage, Shinier HairRated 5 out of 5 stars2 days agoAwesome!
This changed my hair on the first use. I can’t believe I just discovered it. I have hi-lights and low-lights. 30% gray. Medium thickness fine texture. It does not weigh my hair down. Makes it look shiny and healthy. It is lasting. I used it the first six washes after the chemical service. Works like a charm. I LOVE the Limited Edition fragrance. I HOPE they will continue offering it, PLEASE!!
KK18Hair2 days agoThank you so much for your wonderful review, Amber! 🤍 We're thrilled the Jumbo Leave-In Mask is delivering such amazing results for your hair and that you're loving the Limited Edition fragrance. We truly appreciate you being part of the K18 community!