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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 5909 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.
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 5909 reviews
  • 5 Stars
    4818 Reviews
  • 4 Stars
    571 Reviews
  • 3 Stars
    239 Reviews
  • 2 Stars
    115 Reviews
  • 1 Star
    166 Reviews
92% of reviewers would recommend this product to a friend
Customer photos and videos
5909 Reviews
Reviewed by Allison P.
Verified Buyer
I recommend this product
Age
18 - 24
Hair Concern
  • Split-Ends
  • Fragile/brittle hair
  • Dryness
  • Heat damage
Hair Type
  • Fine/Thin
  • Straight/Wavy
My Results
  • Visible Difference
  • Less Breakage
  • Smoother Hair
  • Soft Touchable Hair
Rated 5 out of 5
Review posted

It truly works

It took about 3 weeks for me to see a difference using this product! I wash my hair 2-3 times a week and use it every time I wash. This product is not cheap by any means, but is worth every penny if you are looking to repair damaged hair!

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K18Hair

Thank you for your review Allison!

Reviewed by Hannah M.
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

Best leave in Mask!!

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

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Reviewed by Amanda D.
Verified Buyer
I recommend this product
Age
45 - 54
Hair Concern
  • Chemical damage
  • Frizz
  • Fragile/brittle hair
  • Color-care
Hair Type
  • Medium Density
My Results
  • Smoother Hair
  • Less Frizz
  • Shinier Hair
  • Stronger Hair
Rated 5 out of 5
Review posted

Truly works!

I used K18 Hair Mask for the first 5 consecutive times that I washed. Then I followed the instructions to use once every 3-5 washes after the initial treatment. So far I’m loving the manageability, texture has improved a lot and I’ve only used very little styling products which is a huge plus for me! I would recommend giving K18 a try and I will be ordering again that’s for sure!

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K18Hair

Thank you for your awesome review Amanda!

Reviewed by Kelly D.
Verified Buyer
I recommend this product
Age
45 - 54
Hair Concern
  • Chemical damage
  • Heat damage
  • Color-care
  • Fragile/brittle hair
  • Split-Ends
Hair Type
  • Thick/Coarse
My Results
  • Visible Difference
  • Less Breakage
  • Soft Touchable Hair
  • Less Frizz
Rated 5 out of 5
Review posted

K18

I was very skeptical because I felt I had tried everything. Because I was so unsure I bought the small 15ml size. After 1st use I could tell a noticeable difference. I think this might be what my hair was missing.

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K18Hair

Thank you for your review Kelly!

Reviewed by Caitlin V.
Verified Buyer
I recommend this product
Age
25 - 34
Hair Concern
  • Chemical damage
  • Heat damage
  • Color-care
  • Frizz
  • Fragile/brittle hair
Hair Type
  • Medium Density
  • Straight/Wavy
My Results
  • Less Frizz
  • Visible Difference
  • Less Breakage
  • Stronger Hair
Rated 5 out of 5
Review posted

THE REAL DEAL

Simply Amazing. My hair was ruined by a “stylist” , she burned off my hair with bleach.. though my hair has been blonde for 10+ years and always so healthy. So about 6 inches of my hair was fried off and it was just a disaster. My life long stylist suggested I try this because 6 months of caring for my hair did not work. Honestly my hair is in the best condition after only using the sample bottle… I am now ordering the large bottle because i need it in my life. It last so long the small bottle lasted me about 30 washes!

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K18Hair

Thank you for your review Caitlin! Our 15mL pump has a smaller pump so every 3 pumps equals to 1 full size pump of our 50mL bottle.

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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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