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leave-in molecular repair hair mask

4-minute leave-in treatment to reverse hair damage
Rated 4.7 out of 5
Based on 5613 reviews

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

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!

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.

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 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.

what you can expect
by damage type

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

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 peptide employs 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.
0%
original strength*
0%
original elasticity*
with just one salon treatment, hair is restored up to
* 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.
when using K18 mist and mask as part of a bleaching treatment
*Results observed in a clinical study. Results may vary depending on hair type, quality, and history.
the more damaged the hair, the more dramatic the results
*Results observed in a clinical study. Results may vary depending on hair type, quality, and history.

renews strength, softness, smoothness, and bounce

K18 strengthens hair’s core structure, restoring damaged curl patterns and leaving strands looking and feeling like new.
K18 reconnects broken keratin chains, restoring hairs elasticity and strength meaning coily hair can be renewed and brought back to its original springy, healthy shape.
K18 restores strength, softness, smoothness, and bounce so even the sleekest hair can feel like new.
reviews
average rating 4.7 out of 5
Based on 5613 reviews
  • 5 Stars
    4569 Reviews
  • 4 Stars
    550 Reviews
  • 3 Stars
    227 Reviews
  • 2 Stars
    110 Reviews
  • 1 Star
    157 Reviews
92% of reviewers would recommend this product to a friend
Customer photos and videos
5613 Reviews
Reviewed by Brittany W.
Verified Buyer
Leave-In Molecular Repair Hair Mask 50 mL (WHOLESALE)
Reviewing
Leave-In Molecular Repair Hair Mask 50 mL (WHOLESALE)
I recommend this product
Age
35 - 44
Hair Concern
  • Fragile/brittle hair
  • Dryness
  • Split-Ends
  • Frizz
Hair Type
  • Fine/Thin
My Results
  • Less Frizz
  • Bouncy Hair
  • Soft Touchable Hair
  • Less Breakage
Rated 5 out of 5
Review posted

Love

Great treatment! Makes my har so soft. A little goes a long way.

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Reviewed by Susann P.
Verified Buyer
I recommend this product
Age
65+
Hair Concern
  • Frizz
  • Dryness
Hair Type
  • Fine/Thin
My Results
  • Less Frizz
  • Stronger Hair
  • Shinier Hair
Rated 5 out of 5
Review posted

Best conditioner

The K18 has been a game changer for my hair.

It tames the frizz. And conditions the ends.

So my hair looks fuller and healthier. My

hairdresser was very impressed with my results.

And so am I. I will definitely be repurchasing.

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Reviewed by Crystal R.
Verified Buyer
I recommend this product
Age
25 - 34
Hair Concern
  • Heat damage
  • Fragile/brittle hair
  • Split-Ends
  • Dryness
Hair Type
  • Curly/Coily
  • Thick/Coarse
My Results
  • Visible Difference
  • Stronger Hair
  • Less Breakage
  • Soft Touchable Hair
  • Smoother Hair
Rated 5 out of 5
Review posted

Better than olaplex!

Love it! It makes my hair feel healthier and repaired in the first wash! Will be purchasing from now on!

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Reviewed by Lori M.
Verified Buyer
I recommend this product
Age
45 - 54
Hair Concern
  • Chemical damage
  • Heat damage
  • Frizz
Hair Type
  • Thick/Coarse
  • Grey Hair
My Results
  • Stronger Hair
  • Smoother Hair
Rated 5 out of 5
Review posted

The BEST hair product ever.

I have very damaged/bleached hair. K18 is the only product that makes my hair smooth so I can actually brush through it. Honestly, even when my damaged hair is all grown out, I’ll keep using K18. I’m a fan and customer for life!

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Reviewed by kerry C.
Verified Buyer
I recommend this product
Age
45 - 54
Hair Concern
  • Dryness
  • Frizz
Hair Type
  • Medium Density
My Results
  • Visible Difference
  • Smoother Hair
  • Soft Touchable Hair
Rated 5 out of 5
Review posted

LOVE❤️

I tried this for the first time last week. Absolutely loved it. My hair is not damaged but very dry. Have tried so many high end leave in treatments with little success. This product changed my hair on the very first treatment. I will be ordering the full size product!

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Rated 4.7 out of 5
Based on 5613 reviews
4-minute leave-in treatment to reverse hair damage
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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
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