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
- Texture
- Repair
- Appearance
- Value
- Suezanna G.Verified BuyerReviewingLeave-In Molecular Repair Hair Mask Deluxe SampleI recommend this productRated 5 out of 5 stars3 minutes agoLeft hair soft
I followed directions and was terrified to skip the conditioner step but impressed with results. I was amazed with results.
- Alyce H.Verified BuyerReviewingFull-Size Leave-In Molecular Repair Hair Mask 50mLI recommend this productAge 35 - 44Hair Concern DrynessHair Type Curly/CoilyMy Results Defined Curl/Wave Pattern, Smoother Hair, Visible DifferenceRated 5 out of 5 stars14 hours agoSo far I am in love
Ive used this leave in 3 times so far and I can tell a difference in my curls. They are more defined and not as dry. I have coily 4C hair
KK18Hair13 hours agoThank you so much for the love! 💙 We're thrilled to hear you're seeing amazing results with your 4C curls! ✨ We truly appreciate your support!
- RickistVerified ReviewerReviewingFull-Size Leave-In Molecular Repair Hair Mask 50mLI recommend this productAge 55 - 64Hair Concern Heat damage, Fragile/brittle hair, Frizz, DrynessHair Type Fine/ThinMy Results Less Frizz, Stronger Hair, Smoother Hair, Visible Difference, Soft Touchable HairRated 5 out of 5 stars15 hours agoThere's nothing like this
My hairdresser suggested this product, and it's amazing. I get my roots touched up monthly and add in high/low lights often. Aging is wreaking havoc on my hair, and it's getting fuzzier and finer by the minute. This product is the only one I've used that makes my hair more manageable. The price tag shouldn't scare you because the results are worth it (and you're worth it).
KK18Hair14 hours agoThank you so much for the love! 💙 We're thrilled to hear you're loving the Full-Size Leave-In Molecular Repair Hair Mask! Your hairdresser has great taste, and we're so glad it's making a difference for you. ✨
- Catherine M. B.Verified BuyerReviewingFull-Size Leave-In Molecular Repair Hair Mask 50mLI recommend this productAge 65+Hair Concern Fragile/brittle hair, Dryness, FrizzHair Type Fine/ThinMy Results Visible Difference, Smoother Hair, Less FrizzRated 5 out of 5 stars20 hours agoworks well
This mask is easy to use and produces very good results. Going to use it regularly from now on
KK18Hair18 hours agoThank you so much for the 5-star review, Catherine! We're thrilled to hear you're loving the Full-Size Leave-In Molecular Repair Hair Mask and that it's delivering such great results. 💙✨
- Samantha P.Verified BuyerReviewingFull-Size Leave-In Molecular Repair Hair Mask 50mLI recommend this productAge 35 - 44Hair Concern Dryness, Frizz, Split-Ends, Heat damageHair Type Curly/Coily, Medium DensityMy Results Less Frizz, Bouncy Hair, Visible Difference, Stronger Hair, Smoother HairRated 5 out of 5 stars20 hours agoInstant results!
The way my hair instantly got hydrated simply after 3 pumps had me in a state of shock! And after styling, my hair was light and looking healthy!!
KK18Hair19 hours agoThank you so much for the love, Samantha! 💙 We're thrilled to hear you're getting instant results with our Full-Size Leave-In Molecular Repair Hair Mask! ✨