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full-size leave-in molecular repair hair mask

4-minute leave-in treatment to reverse hair damage
Rated 4.6 out of 5
Based on 6248 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

The K18PEPTIDE™ works at the innermost layer of hair, reconnecting polypeptide chains and disulfide bonds broken during bleaching, chemical services, and through heat damage.


By addressing these damage sites at the innermost layer of hair, core strength and elasticity are renewed for strong, smooth, bouncy hair—even after the most extreme damage done in the salon or at home.

key benefits

  • Powered by the patented K18PEPTIDE™, engineered over 10 years in a biotech lab to work on the molecular level to rebuild hair from the inside out in just 4 minutes.
  • Because the K18PEPTIDE™ works at the molecular level, it works on every single hair type
  • Clinically proven to reverse hair damage from: Bleach + Color, Chemical Services, Heat
  • Restores strength, softness, smoothness, and bounce
  • Immediate + progressive results
  • Vegan, color-safe, cruelty-free

how to use

  1. Shampoo, do not condition.
  2. Towel-dry thoroughly.
  3. Begin with 1 pump of K18 mask and add more as needed depending on length, thickness, and condition. Work evenly into hair from ends to roots, one pump at a time, maximum dosage is 3 pumps.
  4. Let sit for 4 minutes. Do not rinse out.
  5. Then comb + style as usual (fine to add heat protectant or styling product now).
  6. Use for the first 4-6 washes, then as needed

how to optimize K18

  • DO clarify before K18 if you’re a heavy product user (demineralize for mineral + metal 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
  • DO use for 4-6 shampoos consecutively for progressive results.
  • 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

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

got questions?

Get started here

how does the K18 mask work?

K18 works as a treatment to reverse damage in 4 minutes. How it works is a lot like makeup vs. skincare. Concealers (i.e. most hair products) temporarily cover up a problem. K18 works like retinol, highly concentrated, working on a deeper level to renew that base health so you can wear less concealer in the future. Pretty cool right?

What is the K18Peptide™?

Our biomimetic peptide mimics hair’s natural structure to seamlessly fit in and reconnect broken keratin chains responsible for hairs core strength and elasticity. As a result of this reconnection it also addresses cleaved disulfide bonds for connection along the Y-axis of hair AND the x-axis or width of hair.

why skip conditioner?

Conditioner leaves a film on the cuticle that blocks our peptide from penetrating into the innermost layers effectively. Once the 4-minute wait time is up, feel free to use a conditioner, a leave-in, or any type of product.

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 ingredients needed to get the peptide where it needs to go. Our unique blend of 3 alcohols functions to open up the hair cuticle so the K18PEPTIDE™ can penetrate the innermost layer of hair, reaching the broken polypeptide chains (keratin chains). Here the alcohol serves as an agent to optimize the hair environment for K18 mask to work on a deeper level and give you the best results.

When should I expect to see results?

Most see results after 2-3 uses. The more damaged the hair, the more dramatic the results so results may vary depending on your hair type + level of damage.
reviews
average rating 4.6 out of 5
Based on 6248 reviews
  • 5 Stars
    5078 Reviews
  • 4 Stars
    596 Reviews
  • 3 Stars
    257 Reviews
  • 2 Stars
    127 Reviews
  • 1 Star
    190 Reviews
92% of reviewers would recommend this product to a friend
Customer photos and videos
6248 Reviews
Reviewed by Veronica M.
Verified Buyer
I recommend this product
Age
55 - 64
Hair Concern
  • Dryness
  • Fragile/brittle hair
Hair Type
  • Fine/Thin
My Results
  • Visible Difference
  • Smoother Hair
  • Less Breakage
  • Soft Touchable Hair
Rated 5 out of 5
Review posted

Best thing ever!!!

It has made a world of difference for my very thin hair. It feels great going in. It doesn’t feel weighed down or coated with silicone or something. I think it’s fantastic!

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Was this helpful?

K18Hair

Thank you for your review Veronica.

Reviewed by Jessica B.
Verified Buyer
I recommend this product
Age
45 - 54
Hair Concern
  • Heat damage
  • Color-care
  • Dryness
Hair Type
  • Medium Density
My Results
  • Soft Touchable Hair
Rated 5 out of 5
Review posted

I was skeptical but

I've tried many different hair revitalization products. K18's mask and peptide shampoo really does work wonders. My hair is baby soft, my scalp feels great. Truly a good product that does what it says it does in its marketing.

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K18Hair

Thank you for your review Jessica!

Reviewed by Vakhtang M.
Verified Buyer
I recommend this product
Age
25 - 34
Hair Concern
  • Frizz
  • Fragile/brittle hair
  • Dryness
Hair Type
  • Straight/Wavy
  • Fine/Thin
My Results
  • Less Frizz
  • Stronger Hair
  • Less Breakage
  • Soft Touchable Hair
Rated 5 out of 5
Review posted

Great mask

I was pretty skeptical at first. My hair feels great after I use it(stronger and so much less breakage).

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K18Hair

Thank you for your review Vakhtang.

Reviewed by Corey R.
Verified Buyer
I recommend this product
Age
55 - 64
Hair Concern
  • Frizz
Hair Type
  • Medium Density
My Results
  • Less Frizz
  • Visible Difference
  • Soft Touchable Hair
  • Smoother Hair
Rated 5 out of 5
Review posted

Worth the money

It works! I bought the larger size…

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K18Hair

Thank you for your review Corey.

Reviewed by Nadine C.
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
Rated 5 out of 5
Review posted

Less is More

I Love this product. It heals the hair from the inside out! I have been a Licensed Professional for 42 years and have tried many products claiming it repairs and heals, but K18 has taken the Crown. Any hair type can benefit! My only thing I would ask is to change the packaging, not enviro friendly and prefer a recyclable pouch.

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K18Hair

Thank you for your review Nadine. We appreciate your feedback and will relay that to the team.

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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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