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Pro leave-in molecular repair hair mask 50mL Pro leave-in molecular repair hair mask pump Leave-In molecular repair hair mask benefits Coily Hair Bounce Professional Molecular Repair Mask swatch 50 mL Before and After Results for Coily Hair K18 Treatment Before and After Results for Wavy Hair with K18 Treatment Before and After Results for K18 treatment Before and After Results for K18 with Balayage
Pro leave-in molecular repair hair mask 50mL
Pro leave-in molecular repair hair mask pump
Leave-In molecular repair hair mask benefits
Coily Hair Bounce
Professional Molecular Repair Mask swatch 50 mL
Before and After Results for Coily Hair K18 Treatment
Before and After Results for Wavy Hair with K18 Treatment
Before and After Results for K18 treatment
Before and After Results for K18 with Balayage

leave-in molecular repair hair mask

4-minute leave-in treatment to reverse hair damage
Rated 4.9 out of 5
Based on 203 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

Professional Only

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more to know

creates hair like new

Traveling into the inner-most layers of hair to reach the core polypeptide chains (keratin chains), our revolutionary patented K18Peptide™ is just the right size and makeup to fit in and reconnect broken keratin chains. You can feel and see the difference with the first use.

See dosage chart for exact usage. For best results, use for the first 4-6 consecutive washes, then every 3-4 washes as needed to maintain hair strength.

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.

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
how to use K18
  • lightener / bleach
  • color
  • keratin straightener
  • relaxer
  • perm
  • thermal reconditioner
  • lightener / bleach
    1. Prep hair by lightly misting with water.
    2. Generously apply K18 PRO mist section by section.
    3. Wait 4 minutes to allow K18 to penetrate hair strands. DO NOT rinse out (this is a good time to mix color or prepare your lightening service.)
    4. Dry hair if needed. Apply the lightener directly on top of K18 PRO mist and process as usual.
    5. Shampoo hair, do not condition. Towel dry thoroughly until about 65% damp.
    6. Start with 1 pump at a time of the K18 PRO mask, spreading it between your hands to evenly distribute the highly concentrated formula (add more as needed to encounter any missed strands. Average use is 2 pumps, most extreme thick or curly–coily hair use 3 pumps max.)
    7. Leave for 4 minutes before styling. DO NOT rinse out.
    8. If toning, apply toner or gloss on top of K18 PRO mask. Process toner or gloss as required. Shampoo and rinse. Towel dry thoroughly. Follow with a secondary application of K18 PRO mask.
    9. Wait 4 minutes before combing, then style, and add product as usual.
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
Write a Review
average rating 4.9 out of 5
Based on 203 reviews
  • 5 Stars
    194 Reviews
  • 4 Stars
    4 Reviews
  • 3 Stars
    2 Reviews
  • 2 Stars
    2 Reviews
  • 1 Star
    1 Review
98% of reviewers would recommend this product to a friend
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203 Reviews
Reviewed by Brittany W.
Verified Buyer
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 Maryann P.
Verified Buyer
I recommend this product
Age
55 - 64
Hair Concern
  • Chemical damage
  • Color-care
  • Dryness
  • Frizz
Hair Type
  • Thick/Coarse
  • Straight/Wavy
  • Medium Density
My Results
  • Stronger Hair
  • Visible Difference
  • Shinier Hair
  • Smoother Hair
  • Less Frizz
Rated 5 out of 5
Review posted

K-18 review

Hair was in excellent condition after just ONE use of K-18! The best product I have used in my many years of hairdressing.

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Reviewed by Kandi A.
Verified Buyer
I recommend this product
Age
25 - 34
Hair Concern
  • Chemical damage
  • Frizz
  • Split-Ends
  • Dryness
Hair Type
  • Medium Density
My Results
  • Less Frizz
  • Less Breakage
  • Soft Touchable Hair
  • Smoother Hair
  • Stronger Hair
Rated 5 out of 5
Review posted

Love K18

I was able to tell a difference after the 1st time using the product. I was always a big olaplex users till I tried K18.

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Was this helpful?

K18Hair PRO

Thank you for your review Kandi!

Reviewed by Charleigh C.
Verified Buyer
I recommend this product
Age
25 - 34
Hair Concern
  • Chemical damage
  • Dryness
  • Heat damage
Hair Type
  • Thick/Coarse
My Results
  • Less Frizz
  • Less Breakage
  • Smoother Hair
  • Visible Difference
  • Bouncy Hair
Rated 5 out of 5
Review posted

Game changer !

I lighten my hair and I started using this regularly and my hair has never felt better !

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Was this helpful?

K18Hair PRO

Thank you for your review Charleigh.

Reviewed by Brittany H.
Verified Buyer
I recommend this product
Age
25 - 34
Hair Concern
  • Chemical damage
  • Dryness
Hair Type
  • Fine/Thin
  • Straight/Wavy
My Results
  • Stronger Hair
  • Less Breakage
  • Soft Touchable Hair
  • Shinier Hair
  • Smoother Hair
Rated 4 out of 5
Review posted

Amazing product

I like the leave in repair hair mask for many reasons, 1, it leaves the hair so smooth even though you don’t condition it, 2, it really does what it says my hair looks and feels amazing . The only thing that I would have to say is with my hair being so fine I use a half a pump because it tends to weigh heavy on my hair . Over all amazing product to have .

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K18Hair PRO

Thank you for your review Brittany.

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K18 Pro Dosage Calculator ×

Type of service

Lightener / Bleach
Color
Perms
Relaxer
Japanese Straightener
Keratin Smoothing Treatment
K18 Treatment
K18 Haircut

Hair length

Short
Medium
Long

Hair Thickness

Fine
Medium
Coarse
Clear All
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!

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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
800-755-7475
www.paramountbeauty.com
Salon Services Pro
USA
800-251-4247
www.salonservicespro.com
Salon Service Group
USA
417-889-5533
www.salonservicegroup.com
Sweis Inc
USA
877-633-1717
www.sweisinc.com
Liquid Assets
USA
225-292-6500
www.liquidassetsllc.com
Salonwax Pro
USA
877-707-8664
salonwaxpro.com
Premier Beauty Supply
USA
847-480-0000
Launching Soon
Warehouse.5 - Scotland
SC
info@warehouse5.co.uk
www.k18hairscotland.com
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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