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mini leave-in molecular repair hair mask

4-minute leave-in treatment to reverse hair damage
Rated 4.6 out of 5
Based on 6854 reviews

A leave-in treatment mask that works on the molecular level to reverse hair damage in just 4 minutes. The K18PEPTIDE™ is clinically proven to repair damage from bleach + color, chemical services and heat* – with immediate and lasting results to restore strength, softness, smoothness and bounce to hair.

11+ billion TikTok views 🔥 

*Disclaimers

Repairs Damage Caused By

  • Bleach + Color Bleach + Color
  • Heat Heat
  • Chemical Services Chemical Services
OR
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more to know

  • K18PEPTIDE™is a biotech-developed peptide that mimics hair's structure to reverse damage by reconnecting polypeptide chains and disulfide bonds broken during bleaching, color and chemical services + heat*.

  • pH-optimized (5.0-6.0) to help minimize cuticle swelling + put hair proteins in their most resilient state

  • Cream format enables easy, lightweight application across all hair types, with detangling and softening benefits

  • Vegan, color-safe, cruelty-free

key benefits

Takes damage repair further – reconnects both polypeptide chains (and as a result, also reconnects disulfide bonds) for strength along the length + width of the hair - offering comprehensive, lasting damage repair

Restores hair from even extreme damage - by working at the innermost layer of the hair, core strength and elasticity are renewed for strong, smooth, bouncy hair

Delivers immediate and lasting results – hair is repaired from the first use and lasts past your next wash, for ongoing reparative benefits

Simplified repair - convenient, leave-in formula works in just 4 minutes, with no extra rinse required

Works on all hair types – because K18PEPTIDE™ works on a molecular level (where all hair is the same), this product is effective on all hair types

how to use

  1. Shampoo, do not condition.
  2. Towel-dry thoroughly.
  3. Begin with 3 pumps and add more as needed. Maximum recommended usage is 9 pumps.
  4. Apply all over, 1 pump at a time.
  5. Let sit for 4 minutes. Do not rinse out.
  6. Comb, add product + style as usual.
  7. Use for 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.

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Rated 4.8 out of 5
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PEPTIDE PREP™ detox shampoo

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Description

A leave-in treatment mask that works on the molecular level to reverse hair damage in just 4 minutes. The K18PEPTIDE™ is clinically proven to repair damage from bleach + color, chemical services and heat* – with immediate and lasting results to restore strength, softness, smoothness and bounce to hair.

11+ billion TikTok views 🔥 

*Disclaimers
Image Comparison Drag Handle
see molecular repair in action
The K18 leave-in molecular repair hair mask delivers lasting + progressive results, for healthier hair with each use.

the experts know

Groundbreaking PRO stylists, scientists + beauty experts have unlocked new levels of expression with K18 molecular repair.

got questions?

Get started here.

how does the k18 mask work?

The K18 mask works as a treatment to reverse damage in 4 minutes. It’s powered by our biomimetic K18PEPTIDE™ to seamlessly fit in and reconnect broken polypeptide chains at the molecular level. As a result, disulfide bonds are also reconnected for reinforced strength along the length + width of hair—offering comprehensive, lasting, and progressive repair.

what is the k18peptide™?

K18PEPTIDE™ is a biotech-developed peptide that mimics hair’s structure to reverse damage by reconnecting polypeptide chains and disulfide bonds broken during damage from bleach + color, chemical services, and heat*
*Disclaimers

why skip conditioner?

Conditioner leaves a film that blocks our peptide from penetrating 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 amount of ingredients needed to get the peptide where it needs to go. Here the alcohol serves as an agent to optimize the hair environment for the K18 mask to work on a deeper level. Our unique blend of 3 alcohols functions to open the hair cuticle so the K18PEPTIDE™ can penetrate the innermost layer of hair, reaching the broken polypeptide chains (keratin chains).

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 it may vary depending on your hair type and level of damage.
reviews
average rating 4.6 out of 5
Based on 6854 reviews
  • 5 Stars
    5577 Reviews
  • 4 Stars
    650 Reviews
  • 3 Stars
    288 Reviews
  • 2 Stars
    136 Reviews
  • 1 Star
    203 Reviews
92% of reviewers would recommend this product to a friend
Customer photos and videos
6854 Reviews
Reviewed by Tamini “Tami” S.
Verified Reviewer
I recommend this product
Age
35 - 44
Hair Concern
  • Chemical damage
  • Heat damage
  • Frizz
Hair Type
  • Straight/Wavy
  • Fine/Thin
My Results
  • Less Frizz
  • Bouncy Hair
  • Visible Difference
  • Soft Touchable Hair
  • Less Breakage
Rated 5 out of 5
Review posted

Saved my hair!!

I have bleached my hair on and off for years. Whether it was highlights or feeling spicy and doing a peekaboo. I used this today and OMG!! My hair looks absolutely amazing !! The best it’s looked in years and this is just after one use. I can’t wait to see after a month. Forever using this 😊❤️

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

Incredible!

I have natural black hair and frequently lighten it with bleach and apply heat. The very blonde face framing “money pieces” I have break terribly and are visibly fried (curly and split at the ends). I hate the way it looked so I order this product and I’m so glad I did. After 4 uses the hair is very noticeably healthier and no longer has the fried curled look at the bottom. Totally recommend!

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Reviewed by Brenda O.
Verified Buyer
I recommend this product
Age
45 - 54
Hair Concern
  • Chemical damage
  • Heat damage
  • Frizz
  • Dryness
Hair Type
  • Thick/Coarse
My Results
  • Less Frizz
  • Visible Difference
  • Less Breakage
  • Smoother Hair
  • Soft Touchable Hair
Rated 5 out of 5
Review posted

The best!

I’ve used many hair products that claim they help repair damage but there is a noticeable difference with this one. My hair looks and feels healthier every time I use it.

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Reviewed by Yanitza R.
Verified Buyer
I recommend this product
Age
35 - 44
Hair Concern
  • Chemical damage
  • Heat damage
  • Frizz
  • Color-care
  • Dryness
Hair Type
  • Medium Density
  • Straight/Wavy
My Results
  • Visible Difference
  • Stronger Hair
  • Smoother Hair
  • Shinier Hair
  • Soft Touchable Hair
Rated 5 out of 5
Review posted

Amazing

My hair is very thick, damaged and gets frizzy in humid conditions. i have to do deep conditioning treatments and keratin treatments quarterly. After four minutes my hair looked how it looks after a keratin treatment. Totally worth the money!

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K18Hair

Thank you Yanitza! We appreciate your reveiw!

Reviewed by Maddie
Verified Reviewer
I recommend this product
Age
18 - 24
Hair Concern
  • Chemical damage
  • Fragile/brittle hair
  • Dryness
  • Split-Ends
  • Heat damage
Hair Type
  • Fine/Thin
My Results
  • Visible Difference
  • Less Breakage
  • Smoother Hair
  • Soft Touchable Hair
  • Stronger Hair
Rated 5 out of 5
Review posted

Life changer!

I literally need a bucket of this stuff. Out of the millions of hair products I’ve used this stuff Is like no other

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K18Hair

Thank you Maddie for your review!

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