K18 Leave-In Molecular Repair Hair Mask, Patented, Lasting Repair For Dry, Frizzy, Damaged Hair, Reverse Damage In 4 Minutes From Bleach, Color, Chemical Services + Heat

K18 Leave-In Molecular Repair Hair Mask, Patented, Lasting Repair For Dry, Frizzy, Damaged Hair, Reverse Damage In 4 Minutes From Bleach, Color, Chemical Services + Heat

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$74.90
$74.90 $85.90
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K18 Leave-In Molecular Repair Hair Mask, Patented, Lasting Repair For Dry, Frizzy, Damaged Hair, Reverse Damage In 4 Minutes From Bleach, Color, Chemical Services + Heat
$74.90
$74.90 $85.90
SAVE 12% Sold out

how to use

  1. Shampoo, do not condition. Towel-dry thoroughly.
  2. Apply 1-3 pumps of K18 leave-in molecular repair hair mask 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

  • K18PEPTIDE™ 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) to help minimize cuticle swelling + put hair proteins in their most resilient state.
  • Cream format 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 damage - 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 repair - convenient, leave-in formula works in just 4 minutes, with no extra rinse required.

Works on all hair types – because K18PEPTIDE™ 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 it—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 (K18PEPTIDE™), 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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soft, strong, bouncy hair for everyone

Repair damage for hair like new* in 4 minutes.

  • "I absolutely love this product!! You have to see it to believe it!"- Christina Marie P.

  • "Amazing the way it feels and the shineprovides to the hair instantly."- Sandra M.

  • "I've been using this mask for aboutfour washes so far. I feel that my hair isgetting healthier."- Olga S.

  • "I really like it, I was able to tint my hairagain and it looks a little more thicker."- Estefania M.

  • "I use this alllll the time. It's truly savedmy hair....And it's so gorgeous andshiny and the thickness is returningnicely."- Emma L.

  • "My hair has been a mess for years...My new hair stylist recommended K18!... My hair looks and feels amazing withlasting results!!" - Arnell M
    •  

      powered by K18 PEPTIDE™

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

    CLINICALLY PROVEN BENEFITS

    🏆 2022 Allure Best of Beauty Award Winner

    • Patented K18PEPTIDE™
      Reverses damage from bleach, color, chemical services + heat at the molecular level.
    • Works in 4 minutes
      Fast-acting repair. Just wait 4 minutes before styling.
    • Highly concentrated formula
      A little goes a long way. Start with 1 pump and build as needed.
    • Easy leave-in, no rinse needed
      Skip the conditioner. Apply to damp hair and let the peptide do the work.
    • For all hair types
      Universal repair for fine, thick, curly, or straight hair.
    • Vegan + cruelty-free
      Clean, conscious hair science you can feel good about.

    HAIR LIKE NEW IN 4 MINUTES*

    See the K18PEPTIDE™ in action. Even after 8 extreme bleaching sessions, K18 works at the molecular level to restore core strength, softness, and elasticity.

    Real science. Real results. No heavy silicones hiding the damage.

    HOW TO MAXIMIZE YOUR K18 REPAIR:

    Skip the Conditioner: This is crucial. Conditioner leaves a film on your hair that blocks the K18PEPTIDE™ from penetrating. Shampoo, rinse, and go straight to towel-drying.

    Towel-Dry Thoroughly: Your hair should be damp, not dripping wet. Excess water dilutes the formula.

    Wait the Full 4 Minutes: Do not rinse it out. Give the peptide exactly 4 minutes to activate and reconnect the broken keratin chains before you apply any other styling products or heat.

    LESS IS MORE: A HIGHLY CONCENTRATED FORMULA

    This isn't your typical heavy hair mask. The K18 Molecular Repair Mask is a highly concentrated, biotech-powered treatment. Because it penetrates deep into the inner layers of your hair instead of just coating the surface, you need significantly less product than traditional conditioners. Using too much won't increase the repair—it will just weigh your hair down.

    For the Standard Size (50ml):

    • The Golden Rule: Start with just 1 PUMP.
    • How to Build: Emulsify the product in your hands until it turns white, then apply from ends to roots. If your hair is exceptionally thick or long, add an extra half-pump at a time.
    • (Average use: 2 pumps per treatment.)

    For the Mini Size (15ml):

    • The Golden Rule: Start with 3 PUMPS (the mini pump dispenses less).
    • How to Build: Work it evenly through damp, towel-dried hair. Add more only if necessary to ensure all hair is lightly coated.
    • (Average use: 6 pumps per treatment.)

    Customer Reviews

    • Kaya

      Yes yes yes!!! A LITTLE GOES A LONG WAY!!!! I coat the ends of my hair in this IN THE SHOWER AFTER I SHAMPOO. It's great. Makes my hair smooth immediately. I keep it in for 4 minutes before I rinse it and use conditioner. It's not too thick so you're surprised to see how far 2 pumps go. It's a strong formula that adds shine and really helps with your hair health.

      Verified Purchase

    • Customer

      I have used the k18 twice now and I can see improvement on my hair; it has made it more shiner and it feels smooth. The scent smells a little weird, but it not unbearable. I’ve attached photos so you can see the before and after for only two uses so far! The one in the gray and blue top was before using k18, the one in the black is after using k18

      Verified Purchase

    • Brittany Willis

      I love this stuff so much! If it wasn't so expensive, I would use it every single wash. It's the secret sauce for your hair. Pure magic. I bought the small size, without knowing exactly how small it was, so I've added a photo for reference. Would be great if you travel a lot.



      Verified Purchase

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      Got Questions?

      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.