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Leave-In Molecular Repair Hair Mask 5mL
Leave-In Molecular Repair Hair Mask 5mL
4.7
Rated 4.7 out of 5 stars
9,189 Reviews

leave-in molecular repair hair mask

4-minute leave-in treatment to reverse hair damage

Size:
5 mL
Regular price $0
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Leave-In Molecular Repair Hair Mask 5mL

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description

A leave-in treatment mask for all hair types that clinically reverses damage in 4 minutes. The patented peptide technology works to repair damage from bleach, color, chemical services & heat – restoring strength, softness, smoothness, and bounce to hair.

Repairs Damage Caused By

Bleach + Color

Heat

Chemical Services

    • 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.

    • key benefits

      Our K18Peptide™ is clinically proven to reverse damage in just 4 minutes.


      • Heals damage from bleach, color, chemical services, and heat
      • Restores strength, softness, smoothness, and bounce
      • Doesn’t wash away with shampoo, leaving lasting results
      • Vegan, color-safe, cruelty-free



      up to 91% original strength*

      up to 94% original elasticity*


      * Results observed in a clinical study while using mist and mask as part of a bleaching treatment. Results may vary depending on hair type, quality and history.

    • do's + don'ts
      • DO use a clarifying shampoo if you’re a heavy product or dry shampoo user to remove buildup and help our peptide penetrate and get where it needs to go.
      • DO wait the full 4 minutes before styling or applying other product
      • DO use every 4-6 shampoos consecutively to see and feel ongoing results
      • DON’T condition your hair before application (trust us, most won’t need it after K18, if you still need, add a leave-in after the 4-minute window is up post-application)
      • DON’T overuse, a little goes a long way.
      • DON’T rinse out. This is a leave-in, so you know, leave it in!
    • more to know

      creates hair like new


      Traveling deeper into the inner layers of hair than traditional repair products, our revolutionary patented K18Peptide™ is just the right size and makeup to fit in and reconnect broken keratin chains, renewing hair with strength, softness, smoothness, and bounce. You can feel and see the difference with the first use.

      Start by using K18 after the first 4-6 washes. Then switch to maintenance mode for a boost of renewed strength, softness, smoothness, and bounce when needed.

    • how to use

      **IN the shower**
      1. Shampoo, do not condition.

      **OUT of the shower**
      1. Towel dry thoroughly.
      2. Begin with 1 pump of the K18 Mask and add more as needed depending on the length, thickness, and condition.
      3. Work evenly into hair from ends to roots, one pump at a time.
      4. Let sit for 4 minutes to activate.
      5. Do NOT rinse out.
      6. Style as usual.

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Leave-In Molecular Repair Hair Mask 5mL
Leave-In Molecular Repair Hair Mask 5mL
feel what's possible with K18

See how K18 unlocks our community's expression

4.7
Rated 4.7 out of 5 stars
Based on 9,189 reviews
93%would recommend these products
Reviews Summary
Customers say this leave-in hair mask transforms their hair texture and manageability after just one use. Many reviews mention noticeable improvements in softness and reduced frizz. Users with curly, fine, and color-treated hair report positive results. The mask works well for various hair types, with many noting improved texture and easier styling. While some mention the product's high price point, most find a little goes a long way. A few users recommend using conditioner alongside the mask for best results. Reviews consistently highlight the mask's effectiveness for addressing dry, brittle hair concerns.
Customers Talked About
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9,189 reviews
  • Jill D.
    Verified Buyer
    Reviewing
    Full-Size Leave-In Molecular Repair Hair Mask 50mL
    I recommend this product
    Age 55 - 64
    Hair Concern Heat damage, Chemical damage, Frizz, Fragile/brittle hair
    Hair Type Thick/Coarse, Straight/Wavy
    My Results Visible Difference, Soft Touchable Hair, Less Breakage, Less Frizz, Stronger Hair
    Rated 5 out of 5 stars
    5 days ago
    Love this product!

    I have long, thick, bleached blonde hair. My best friend is a hair stylist, so I always use professional products and have always had beautiful blonde hair! However, I made the mistake of straightening it without a heat protector or leave in, because I was in a hurry one day and I literally fried my hair, because the straightener was on 450*! So I was told by my best friend to use the K18 hair repair mask, but I was hesitant because of the price of the small full size bottle. However ,I trust my hair stylist, so I purchased it. The first time using it I could feel and see a huge difference and I couldn’t believe it? I did have to use 4 pumps because of the length and thickness of my hair, but after 6 times using it in a row and after having a stem cell treatment done, my hair is back to Beautiful! I will definitely continue to incorporate this product into my weekly hair maintenance routine.

    Was this helpful?
    K Profile picture for K18Hair
    K18Hair
    5 days ago

    Thank you so much for your review, Jill! 🤍 We're thrilled the Molecular Repair Hair Mask has helped restore your hair to beautiful after heat damage. We're so grateful for your trust and so happy you're making it part of your routine!

  • Rachel K.
    Verified Buyer
    Reviewing
    Jumbo Leave-In Molecular Repair Hair Mask 100mL
    I recommend this product
    Age 25 - 34
    Hair Concern Chemical damage, Color-care, Split-Ends, Fragile/brittle hair
    Hair Type Fine/Thin, Medium Density
    My Results Visible Difference, Stronger Hair, Less Breakage, Defined Curl/Wave Pattern
    Rated 5 out of 5 stars
    6 days ago
    Essential

    As someone who dyes their hair blonde, K18 has helped it stay healthy and growing! I’m obsessed!

    Was this helpful?
    K Profile picture for K18Hair
    K18Hair
    5 days ago

    Thank you so much for your review, Rachel! 🤍 We're thrilled the Jumbo Leave-In is helping keep your blonde hair healthy and strong. We appreciate you being part of the K18 community!

  • Yuliya B.
    Verified Buyer
    Reviewing
    Full-Size Leave-In Molecular Repair Hair Mask 50mL
    I recommend this product
    Age 45 - 54
    Hair Concern Color-care
    Hair Type Fine/Thin
    My Results Visible Difference, Less Breakage
    Rated 5 out of 5 stars
    6 days ago
    My Hair Feels So Much Healthier

    I’ve been using this hair mask for a while, and I’m really happy with the results. My hair has become more resilient and much less prone to breakage. It feels softer, smoother, and healthier, with a beautiful shine. My ends look more nourished, and my hair is much easier to brush after every use. I definitely recommend this mask, especially for damaged or color-treated hair. I’ll definitely buy it again!

    Was this helpful?
    K Profile picture for K18Hair
    K18Hair
    6 days ago

    Thank you so much for your wonderful review! 🤍 We're thrilled to hear the Molecular Repair Hair Mask is delivering such amazing results for your hair. We truly appreciate you being part of the K18 community!

  • Melyssa G.
    Verified Buyer
    Reviewing
    Jumbo Leave-In Molecular Repair Hair Mask 100mL
    I recommend this product
    Age 25 - 34
    Hair Concern Chemical damage, Heat damage, Color-care, Fragile/brittle hair, Dryness
    Hair Type Medium Density
    My Results Visible Difference, Stronger Hair, Less Breakage, Smoother Hair, Bouncy Hair
    Rated 5 out of 5 stars
    1 week ago
    K18 SAVED MY HAIR

    This product single handily saved my hair from extreme bleach damage and breakage, I couldn’t see the end of the tunnel and my hair is finally growing again and has movement to it and retains moisture, after a bleach accident I truly never thought I would be able to see my hair this healthy again without losing my blonde, it’s almost healthier than what it used to be when it was virgin hair, it’s extremely soft and bouncy🥹 i will ALWAYS repurchase this!

    Was this helpful?
    K Profile picture for K18Hair
    K18Hair
    1 week ago

    Thank you so much for your review, Melyssa! We're absolutely thrilled to hear the Jumbo Leave-In Molecular Repair Hair Mask has helped restore your hair's health and strength. Your support means everything to us, and we're so grateful you're part of the K18 community!

  • Ilena C.
    Verified Buyer
    Reviewing
    Leave-In Molecular Repair Hair Mask Deluxe Sample
    I recommend this product
    Rated 5 out of 5 stars
    2 weeks ago
    Great product.

    I’ve been using this product for several weeks now, and I’ve noticed my hair feels softer, smoother, and healthier. The jumbo size is a good value if you plan to use it regularly. I’m happy with the results and would recommend it to anyone looking to improve the look and feel of their hair.

    Was this helpful?
    K Profile picture for K18Hair
    K18Hair
    2 weeks ago

    Thank you so much for your review! We're thrilled to hear the Leave-In Molecular Repair Hair Mask has left your hair feeling softer and smoother. We truly appreciate your support and are grateful you're part of the K18 community!

*Disclaimers

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