Rating 8,389 Reviews

Full-Size Leave-In Molecular Repair Hair Mask 50mL

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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 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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*Disclaimers

Repairs Damage Caused By

  • Bleach + Color
  • Heat
  • Chemical Services
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Color-safe, non-stripping clarifying shampoo with the K18PEPTIDE™
Full-Size Leave-In Molecular Repair Hair Mask 50mL

Full-Size Leave-In Molecular Repair Hair Mask 50mL

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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.
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
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.
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).
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.
powered by K18PEPTIDE™

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

learn more on our blog
4.6
Rated 4.6 out of 5 stars
Based on 5 reviews
5 reviews
  • Lucy S.
    Verified Buyer
    I recommend this product
    Age 55 - 64
    Hair Concern Chemical damage, Heat damage, Color-care, Frizz, Fragile/brittle hair
    Hair Type Thick/Coarse
    My Results Visible Difference, Smoother Hair, Less Frizz, Less Breakage, Stronger Hair
    2 days ago
    Absolutely the BEST!

    This product is the best for dry course damage over processed hair. Put on towel, dried hair and blow dry and style as usual and your hair is more silky, smooth than ever imaginable!

    K Profile picture for K18Hair
    K18Hair
    2 days ago

    We're so thrilled to hear this, Lucy! Thank you for sharing your experience with this incredible formula!

  • Melissa W.
    Verified Buyer
    I recommend this product
    Age 35 - 44
    Hair Concern Heat damage
    Hair Type Fine/Thin
    3 days ago
    Scent mask

    It’s not overpowering and fantastic change up from the original with all the great benefits of the mask!

    K Profile picture for K18Hair
    K18Hair
    2 days ago

    It's wonderful to hear that the limited edition scent gives you that perfect balance - a fantastic change from the original without being overpowering, while still delivering all those amazing mask benefits! Thank you for sharing your experience with this special formula, Melissa!

  • Christine L.
    Verified Buyer
    I recommend this product
    Age 55 - 64
    Hair Concern Chemical damage, Heat damage, Frizz, Split-Ends, Dryness
    Hair Type Medium Density, Straight/Wavy
    My Results Less Frizz, Visible Difference, Less Breakage, Smoother Hair, Stronger Hair
    5 days ago
    The Best for Damaged Hair

    I tried this product many years ago and wasn’t really thrilled with it. However, my hairdresser continues to use many of their products and loves them. So I decided to give it another try and ordered it directly from the K-18 website. I’m not sure but I think the first time I tried it. I didn’t buy it directly from them and I think it may not have been authentic. Because this time when I tried it, it was excellent. First, I tried a small bottle and now I got a bigger bottle and I’m thinking I should’ve got the biggest bottle. Really helps with frizzy color damaged hair and split ends. I’m on my third or fourth wash and starting to notice a real difference in the texture of my hair. And it’s also. not getting tangled as much afterwards.

    K Profile picture for K18Hair
    K18Hair
    2 days ago

    We love that you went from the small bottle to the bigger one - that's always a great sign! Thank you for sharing your experience and for trusting us with your hair care journey!

  • ANGIE P.
    Verified Buyer
    I recommend this product
    Age 25 - 34
    Hair Concern Chemical damage, Split-Ends
    Hair Type Medium Density, Straight/Wavy
    My Results Bouncy Hair, Soft Touchable Hair, Shinier Hair, Smoother Hair, Odor eliminated
    1 week ago
    Nonstop compliments

    Used this mask before a girls night and everyone was asking what I was wearing. It's a mysterious, and expensive smell, like what you'd expect from a boutique hotel. It's not overly feminine, with its peppery notes to balance the floral. As a long time mask lover, I might need to go to Future Society to purchase a bottle!

    K Profile picture for K18Hair
    K18Hair
    1 week ago

    We're so excited to hear about all the compliments you received, Angie! It sounds like the limited edition scent was the perfect choice for your girls night. Thank you for sharing your wonderful experience!

  • Andrea
    Verified Buyer
    Age 25 - 34
    Hair Concern Heat damage, Chemical damage, Frizz, Split-Ends, Color-care
    Hair Type Fine/Thin, Straight/Wavy
    My Results Smoother Hair
    1 week ago
    Love the mask but hate the scent

    Wow…. The scent is just bad. Really bad. Not feminine at all. Smells like peppery dirt. I was Looking forward to trying it with a floral woodsy scent but instead it just smells like peppery and dirt … for $75 😭

    K Profile picture for K18Hair
    K18Hair
    1 week ago

    Thank you for sharing your honest feedback. We’re sorry to hear the scent didn’t meet your expectations. Fragrance preference is so individual, and we appreciate you giving the product a try. We went ahead and processed a refund for your order, you should receive an email confirmation shortly.