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leave-in molecular repair hair mask

4-minute leave-in treatment to reverse hair damage
Rated 4.6 out of 5
Based on 6069 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.

11+ billion TikTok views 🔥 

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.

11+ billion TikTok views 🔥 

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.

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 4.6 out of 5
Based on 6069 reviews
  • 5 Stars
    4941 Reviews
  • 4 Stars
    581 Reviews
  • 3 Stars
    249 Reviews
  • 2 Stars
    121 Reviews
  • 1 Star
    177 Reviews
92% of reviewers would recommend this product to a friend
Customer photos and videos
6069 Reviews
Reviewed by Dorothie H.
Verified Buyer
I recommend this product
Age
65+
Hair Concern
  • Frizz
  • Fragile/brittle hair
Hair Type
  • Fine/Thin
My Results
  • Less Frizz
  • Visible Difference
  • Stronger Hair
  • Smoother Hair
  • Shinier Hair
Rated 5 out of 5
Review posted

Give it some time

It took some time for this stuff to work it's magic but it's been worth it. I used to have hairs of different lengths sticking out as if I'd brushed it with a balloon no matter what I did. No more. It is shiny and smooth and beautiful. Highly recommend.

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Reviewed by Barbara B.
Verified Buyer
I recommend this product
Age
55 - 64
Hair Concern
  • Color-care
  • Dryness
Hair Type
  • Fine/Thin
My Results
  • Less Frizz
  • Visible Difference
  • Smoother Hair
  • Shinier Hair
  • Bouncy Hair
Rated 5 out of 5
Review posted

Does what it says

It really does make a difference in my fine, blonde (colored) hair. It looks more substantial and smoothe after use. Really love that it is super easy to use - no leaving it in and waiting around before shampooing, etc. I usually shampoo almost everyday since I run/work out a lot so do need to use this product 2-3 times a week to maintain the effect. Haven’t used it long enough yet to say if it actually strengthens my hair , but do like the instant effects!

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K18Hair

Great photo Barbara, thank you for your review.

Reviewed by Dana F.
Verified Buyer
Leave-In Molecular Repair Hair Mask 15 mL (WHOLESALE)
Reviewing
Leave-In Molecular Repair Hair Mask 15 mL (WHOLESALE)
I recommend this product
Rated 5 out of 5
Review posted

Magical!!!!

This has been such a game changer in my salon and for my clients!!!! Hair is stronger than ever and color is lasting longer! Thank you k18!!!!

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K18Hair

Thank you for your review Dana.

Reviewed by Hillary O.
Verified Buyer
I recommend this product
Age
25 - 34
Hair Concern
  • Heat damage
  • Frizz
  • Fragile/brittle hair
  • Dryness
  • Chemical damage
Hair Type
  • Thick/Coarse
  • Straight/Wavy
My Results
  • Bouncy Hair
  • Defined Curl/Wave Pattern
  • Shinier Hair
  • Soft Touchable Hair
  • Visible Difference
Rated 5 out of 5
Review posted

Miracle in a bottle

My hair has always been very dry and frizzy. I’ve recently found out that it’s actually because I have naturally wavy hair that’s just been damaged and for a while I was trying to get the waves back but it was hard due to how damaged my hair was. After using this a couple of times I can see my wave pattern alot more, my hair looks and feels a lot healthier, moisturized and feels so soft! I def recommend this to anyone!!

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K18Hair

Thank you for your review Hillary!

Reviewed by Lynne T.
Verified Buyer
I recommend this product
Age
65+
Hair Concern
  • Chemical damage
  • Frizz
  • Color-care
  • Fragile/brittle hair
  • Dryness
Hair Type
  • Fine/Thin
My Results
  • Less Frizz
  • Bouncy Hair
  • Visible Difference
  • Stronger Hair
  • Less Breakage
Rated 5 out of 5
Review posted

Amazing!!!

I love that all o have to do is wash my hair in the shower. It's so easy and leaves my hair beautiful. I used it with my own shampoo the first time, but then I used K18 Shampoo and I couldn't believe how much better it worked. Thank you

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K18Hair

Thank you for your review Lynne!

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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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