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full-size leave-in molecular repair hair mask

full-size leave-in molecular repair hair mask

4-minute leave-in treatment to reverse hair damage

Regular price $75.00
Regular price $75.00 Sale price $99.99
SAVE 24% Sold out
 

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Description

A leave-in treatment mask that works on the molecular level to reverse hair damage in just 4 minutes*. The K18PEPTIDEβ„’ 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.

Repairs Damage Caused By

Bleach + Color

Heat

Chemical Services

how to use

  1. Shampoo, do not condition. Towel-dry thoroughly.
  2. Apply 1-3 pumps ofΒ K18 leave-in molecular repair hair maskΒ 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 product + style as usual. Use for 4-6 washes post-salon service, then as needed.

more to know

  • K18PEPTIDEβ„’Β is a biotech-developed peptide that mimics hair's structure to reverse damage by reconnecting polypeptide chains and disulfide bonds broken during bleaching, color and chemical services + heat*.
  • pH-optimized (5.0-6.0)Β to help minimize cuticle swelling + put hair proteins in their most resilient state.
  • Cream formatΒ enables easy, lightweight application across all hair types, with detangling and softening benefits.
  • Vegan, color-safe, cruelty-free.

key benefits

Takes damage repair further – reconnects both polypeptide chains (and as a result, also reconnects disulfide bonds) for strength along the length + width of the hair - offering comprehensive, lasting damage repair.

Restores hair from even extreme damageΒ - by working at the innermost layer of the hair, core strength and elasticity are renewed for strong, smooth, bouncy hair.

Delivers immediate and lasting results – hair is repaired from the first use and lasts past your next wash, for ongoing reparative benefits.

Simplified repairΒ - convenient, leave-in formula works in just 4 minutes, with no extra rinse required.

Works on all hair types – becauseΒ K18PEPTIDEβ„’Β works on a molecular level (where all hair is the same), this product is effective on all hair types.

dos and don'ts

  • DO clarify before K18 if you’re a heavy product user (demineralize for mineral + metal buildup).
  • DO apply on clean, damp hair.
  • DO wait the full 4 minutes before combing or styling.
  • DO add whatever styling products you love after the 4 minutes.
  • DO use for 4-6 shampoos consecutively for progressive results.
  • DON'T use conditioner before applying K18 Mask (you can apply after the 4 min but most find they don’t need it).
  • DON'T overdo itβ€”less is more.
  • DON'T rinse it out.

ingredients

Water (Aqua) (Eau), Alcohol Denat., Propylene Glycol, Cetearyl Alcohol, Dicaprylyl Ether, Cetyl Esters, Behentrimonium Chloride, Polysorbate 20,sh-Oligopeptide-78 (K18PEPTIDEβ„’), Hydrolyzed Wheat Protein, Hydrolyzed Wheat Starch, Isopropyl Alcohol, Tocopherol, Phenoxyethanol, Potassium Sorbate, Citric Acid, Fragrance (Parfum), Geraniol, Linalool, Hexyl Cinnamal, Benzyl Alcohol.

 
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full-size leave-in molecular repair hair mask

full-size leave-in molecular repair hair mask

Regular price $75.00
Regular price $75.00 Sale price $99.99
SAVE 24% Sold out
View full details

    Get started here.

    got questions?

    help

    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 K18PEPTIDEβ„’ 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 hairβ€”offering comprehensive, lasting, and progressive repair.

    help

    what is the k18peptideβ„’?

    K18PEPTIDEβ„’ 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*

    help

    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.

    help

    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 K18PEPTIDEβ„’ can penetrate the innermost layer of hair, reaching the broken polypeptide chains (keratin chains).

    help

    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.

    • β˜…β˜…β˜…β˜…β˜…



      "I absolutely love this product!! You have to see it to believe it!"






      Christina Marie P.

    • β˜…β˜…β˜…β˜…β˜…

      "...I had my hair chopped (it was begging for it) along with some highlights and coloring of the roots. My hair stylist used this on my hair and I absolutely loved how it made my hair feel ... I love this product so much!"



      Ashley P.

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      "Amazing the way it feels and the shine provides to the hair instantly."





      Sandra M.

    • β˜…β˜…β˜…β˜…β˜…



      "l've been using this product for about four washes so far. I feel that my hair is getting healthier."





      Olga S.

    • β˜…β˜…β˜…β˜…β˜…

      "It makes my hair so soft and weightless, I absolutely love it. Most of the product leave my hair greasy and I can't even style it, and right after washing I have to put it in the bun. It's a nightmare! But not with k-18. Makes my hair feel so luxurious, it's like I just left the salon. Can't recommend this product more!"

      Anastasiia T.

    • β˜…β˜…β˜…β˜…β˜…


      "My hair has been a mess for years... My new hair stylist recommended K18!... My hair looks and feels amazing with lasting results!!"




      Arnell M

    • β˜…β˜…β˜…β˜…β˜…


      "I have heat damaged color treated curly hair and this has improved my hair health immensely...This is one of those products that has incorporated itself into my routine for the rest of my life..."



      Siria A.

       

      powered by K18PEPTIDETM

      Biomimetic peptide clicks into hair's keratin structure-the source of core strength-for soft,

      shiny, bouncy results that won't wash away.

      how to use molecular repair mask

      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

        Why You'll Love It

        • Repairs damage in as little as 4 minutes
        • Helps restore strength, elasticity, and flexibility
        • Improves softness and smoothness
        • Reduces breakage caused by chemical and heat damage
        • Leaves hair feeling lightweight and healthy
        • Suitable for all hair types and textures
        • Color-safe and chemically treated hair friendly
        • Vegan and cruelty-free
        • No rinsing required

        Advanced Molecular Hair Repair

        Healthy hair depends on strong internal protein structures. Over time, bleaching, coloring, heat styling, UV exposure, and chemical services weaken these structures, resulting in brittle, dull, and lifeless hair.

        The K18 Leave-In Molecular Repair Hair Mask is formulated with K18PEPTIDEβ„’ , a biomimetic peptide engineered to help reconnect broken keratin chains deep within the hair. Rather than masking damage temporarily, it works where damage occurs, supporting healthier-looking hair that feels stronger, smoother, and more resilient after continued use.

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