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leave-in molecular repair hair mask

4-minute leave-in treatment to reverse hair damage
Rated 4.9 out of 5
Based on 117 reviews

A leave-in treatment mask for all hair types that 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.

11+ billion TikTok views 🔥

Repairs Damage Caused By

  • Bleach + Color Bleach + Color
  • Heat Heat
  • Chemical Services Chemical Services

Professional Only

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more to know

The K18 mask is engineered to do cleanup duty after bleach + color, chemical services, and heat—restoring strength + elasticity to damaged strands. Lightweight conditioning benefits give your clients smooth, soft, strong, and bouncy hair, even after all the damage done in the salon.

Damage is ongoing

Send the K18 retail sizes home with your client to keep hair health going, make services last longer, and strengthen their canvas so you can go further during the next appointment.

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.

do's + don'ts

  • Do clarify before K18 if you’re a heavy product user (demineralize for hard water 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
  • 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

key benefits

  • Infused with our patented K18PEPTIDE™ to reverse damage in just 4 minutes.
  • Repairs damage from bleach + color, chemical services, and heat.
  • Restores strength, softness, smoothness, and bounce for all hair types.
  • Lasting + progressive results get better with continued use
  • Vegan, color-safe, cruelty-free
  • 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.

    Description

    A leave-in treatment mask for all hair types that 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.

    11+ billion TikTok views 🔥

    backed by science,
    loved by stylists

    Our community of stylists and colorists believe K18 is liberating hair—no matter the hair type or generation.

    “K18 allows me to go everywhere I want to go with my color work and the end result is my guests get to be bright and shiny and healthy.”

    – Christine Thompson, Director of Color at Spoke & Weal
    pros using K18

    how K18 works

    Traveling into the innermost layers of hair, our K18PEPTIDE™ renews strength along the width AND length of hair for lasting strength where it matters.

    have questions?

    we have answers.

    How does K18 work?

    When hair gets damaged, the polypeptide chains (keratin chains) that make up the inner structure of hair strands become weakened and break. For context, there are billions and billions of polypeptide chains (keratin chains) in a single strand of hair. When these are damaged, hair’s core structure responsible for elasticity and strength becomes compromised and as a result it loses its resiliency and shine—or the look and feel of healthy hair.

    After spending a decade in the lab scanning and testing all amino acid sequences across the entire keratin genome that makes up human hair searching for a breakthrough, we discovered one unique sequence (a bioactive peptide) that brings damaged hair back to its original, youthful state. This is our K18Peptide™.

    Traveling deeper into the inner layers of hair than traditional repair products, our revolutionary peptide is just the right size and makeup to fit in and reconnect those broken polypeptide chains (keratin chains). And because our peptide is a bit of an overachiever, as a result of this reconnection, any disturbed disulfide bonds are also re-conformed.

    Our peptideemploys biomimetics to get the job done. To put it simply: Biomimetics is the practice of learning from and mimicking nature. Mimicking the natural structure of keratin building blocks (amino acid sequences), our K18 bioactive peptide is recognized as natural by the hair. It’s not washed away by water or shampoo like traditional bonding agents either, making K18 a genuine, lasting solution for damaged strands.

    What is the K18Peptide™?

    Our patented peptide is a unique sequence of amino acids that travels deep into hair’s core structure to fit in and reconnect broken polypeptide chains (keratin chains) responsible for hair strength and elasticity.

    An Analogy: When building proteins, the order of the amino acids determines the kind of protein and its properties, much like the way letters are arranged to make meaningful words and sentences. In the same way the order and where each word sits in a sentence leads to its overall meaning, K18 is the magic word that fits right in, integrating itself with the keratin chains as the hair recognizes it as a natural building block.

    Why should I skip conditioner?

    K18 is most effective on clean, towel-dried hair. Conditioners use silicones and conditioning agents that form heavy coatings on hair , preventing our peptide from reaching the broken polypeptide chains deep inside hair’s inner layer.

    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. Our unique blend of 3 alcohols function to open up the hair cuticle so the K18Peptide ™ can penetrate the inner most layer of hair, reaching the broken polypeptide chains (keratinchains). Here the alcohol serves as an agent to optimize the hair environment for K18 to work on a deeper level.

    When should I expect to see results?

    You will start to see stronger, softer, healthier hair after just one use.
    reviews
    average rating 4.9 out of 5
    Based on 117 reviews
    • 5 Stars
      111 Reviews
    • 4 Stars
      4 Reviews
    • 3 Stars
      1 Review
    • 2 Stars
      0 Reviews
    • 1 Star
      1 Review
    99% of reviewers would recommend this product to a friend
    117 Reviews
    Reviewed by Hannah M.
    Verified Buyer
    I recommend this product
    Rated 5 out of 5
    Review posted

    Best leave in Mask!!

    Love the fact you don’t have to rinse it out!

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    Reviewed by Kristi W.
    Verified Buyer
    I recommend this product
    Rated 5 out of 5
    Review posted

    Best hair mask

    I love using this on clients. They are always amazed by the results.

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    Reviewed by Simone P.
    Verified Buyer
    I recommend this product
    Rated 5 out of 5
    Review posted

    The best

    Best product ever

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    Reviewed by Cassidy L.
    Verified Buyer
    I recommend this product
    Rated 5 out of 5
    Review posted

    Amazing product

    Really loving this product and so are my clients

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    Reviewed by Mayra Aldava E.
    Verified Buyer
    I recommend this product
    Age
    25 - 34
    Hair Concern
    • Chemical damage
    • Heat damage
    • Color-care
    • Fragile/brittle hair
    • Dryness
    Hair Type
    • Thick/Coarse
    My Results
    • Less Frizz
    • Visible Difference
    • Stronger Hair
    • Less Breakage
    • Shinier Hair
    Rated 5 out of 5
    Review posted

    I love this

    I absolutely love it! My clients love how soft hair gets left !

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    K18Hair PRO

    Love the photo Mayra! Thank you for your review.

    Calculating…

    based on your client + service

    DOSAGE CALCULATION

    pre-service

    Apply a generous amount to damp hair, section by section

    post-service

    3 pumps
    throughout the hair

    How to use

    • Prep hair by lightly misting with water.
    • Apply K18 Mist section by section.
    • Wait 4 minutes. DO NOT rinse. (This is a good time to mix or prepare for your Lightening Service.)
    • Apply Lightener directly on top of K18 Mist. (Dry hair if needed prior to application.)
    • Process as usual.
    • Shampoo hair. Skip the conditioner.
    • Towel dry thoroughly.
    • Apply K18 Mask.
    • Leave for 4 minutes before styling. DO NOT rinse out.
    • If toning, apply toner / gloss on top of K18 Mask. Process toner / gloss as required. Shampoo and rinse. Towel dry thoroughly. Follow with secondary application of K18 Mask for 4 minutes.
    • Style as usual.

    client recommendation

    At-Home Treatment

    Leave in Molecular Hair Repair Mask

    2 pumps

    Use for the first 4-6 washes, then every 3-4 washes for ongoing damage repair.

    optimize K18

    skip the conditioner

    Conditioners coat hair making it harder for our K18Peptide™ to effectively penetrate strands and get into the inner layers of hair. We like to skip it so the peptide can get right to damage sites without interruption. If strands need a little more love, you can add a leave-in conditioner once the initial 4-minute wait period is over.

    clarify first

    Excessive product or mineral buildup on hair can prevent our K18Peptide™ from effectively penetrating strands. If hair is heavy with buildup, start with a clarifying treatment before using K18 to remove residue that may block our peptide from getting where it needs to go.

    continue use

    Damage is ongoing, so clients' use of K18 should be too. This progressive treatment makes hair healthier with each use. Continue their hair renewal at home by using K18 for the first 4-6 washes, then every 3-4 washes to maintain the integrity of damaged hair.

    less is more

    Our Pro Mask is highly concentrated, meaning a little goes a long way. Don’t oversaturate hair and refer to our dosage chart to find the optimal amount for each client’s hair type and service.

    more is more

    When using the Pro Mist, the more the merrier to reset damage before a chemical service. Use pre-service for a healthy canvas by applying a generous amount of the Pro Mist to damp hair, section by section.

    made for all

    K18 Pro Mist + Mask are compatible with all products and all hair types regardless of texture, generation, or level of damage.

    optimize K18

    clarify first

    Excessive product or mineral buildup on hair can prevent our K18Peptide™ from effectively penetrating strands. If hair is heavy with buildup, start with a clarifying treatment before using K18 to remove residue that may block our peptide from getting where it needs to go.

    more is more

    When using the Pro Mist, the more the merrier to reset damage before a chemical service. Use pre-service for a healthy canvas by applying a generous amount of the Pro Mist to damp hair, section by section.

    made for all

    K18 Pro Mist + Mask are compatible with all products and all hair types regardless of texture, generation, or level of damage.

    optimize K18

    clarify first

    Excessive product or mineral buildup on hair can prevent our K18Peptide™ from effectively penetrating strands. If hair is heavy with buildup, start with a clarifying treatment before using K18 to remove residue that may block our peptide from getting where it needs to go.

    continue use

    Damage is ongoing, so clients' use of K18 should be too. This progressive treatment makes hair healthier with each use. Continue their hair renewal at home by using K18 for the first 4-6 washes, then every 3-4 washes to maintain the integrity of damaged hair.

    more is more

    When using the Pro Mist, the more the merrier to reset damage before a chemical service. Use pre-service for a healthy canvas by applying a generous amount of the Pro Mist to damp hair, section by section.

    made for all

    K18 Pro Mist + Mask are compatible with all products and all hair types regardless of texture, generation, or level of damage.

    optimize K18

    skip the conditioner

    Conditioners coat hair making it harder for our K18Peptide™ to effectively penetrate strands and get into the inner layers of hair. We like to skip it so the peptide can get right to damage sites without interruption. If strands need a little more love, you can add a leave-in conditioner once the initial 4-minute wait period is over.

    clarify first

    Excessive product or mineral buildup on hair can prevent our K18Peptide™ from effectively penetrating strands. If hair is heavy with buildup, start with a clarifying treatment before using K18 to remove residue that may block our peptide from getting where it needs to go.

    continue use

    Damage is ongoing, so clients' use of K18 should be too. This progressive treatment makes hair healthier with each use. Continue their hair renewal at home by using K18 for the first 4-6 washes, then every 3-4 washes to maintain the integrity of damaged hair.

    less is more

    Our Pro Mask is highly concentrated, meaning a little goes a long way. Don’t oversaturate hair and refer to our dosage chart to find the optimal amount for each client’s hair type and service.

    made for all

    K18 Pro Mist + Mask are compatible with all products and all hair types regardless of texture, generation, or level of damage.

    K18 Pro Dosage Calculator ×
    ×

    Send this to your client!

    Your K18 Hair at-home treatment recommendation is of leave-in molecular repair hair mask for the first 4-6 washes, then every 3-4 washes for ongoing damage repair. For more information on the product and how to use, visit k18hair.com!

    Pro Distribution Partners

    Hair professionals can shop wholesale at the following distributors. Professionals within the US will also be able to shop directly from K18hair.com starting early 2021! Check back again soon for updates as we continue to expand globally.



    Questions? Email us at hello@k18hair.com

    Paramount Beauty Supply
    USA
    Salon Services Pro
    USA
    Salon Service Group
    USA
    Salonwax Pro
    USA
    Premier Beauty Supply
    USA
    Launching Soon
    Ozdare - Australia
    AU
     
    Launching Soon
    American Crew Ltd. - New Zealand
    NZ
     
    Launching Soon
    PlayGround - Hong Kong
    HK
     
    Launching Soon
    Session Map - Sweden
    SE
     
    Launching Soon
    Cyprus
    CY
     
    Launching Soon
    Belgium
    BE
     
    Coming Early 2021
    Canada
    CA
     
    Coming Early 2021
    Czech Republic
    CZ
     
    Coming Early 2021
    Finland
    FI
     
    Coming Early 2021
    France
    FR
     
    Coming Early 2021
    Germany
    DE
     
    Coming Early 2021
    Ireland
    IR
     
    Coming Early 2021
    Italy
    IT
     
    Coming Early 2021
    Netherlands
    NL
     
    Coming Early 2021
    Norway
    NO
     
    Coming Early 2021
    Singapore
    SG
     
    Coming Early 2021
    Taiwan
    TW
     
    Coming Early 2021
    UK
    UK
     
    Coming Early 2021
    thank you for visiting!

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