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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 7434 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.

20+ billion TikTok views 🔥 

*Disclaimers

Repairs Damage Caused By

  • Bleach + Color
  • Heat
  • 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. Towel-dry thoroughly
  2. Apply 3-9 pumps of K18 leave-in molecular repair hair mask based on your length and density, starting at the ends and working up towards the roots
  3. Let sit for 4 minutes. Do not rinse out
  4. Comb, add product + style as usual. Use for 4-6 washes post-salon service, then as needed

dos and don'ts

  • 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.

pairs well with

K18 molecular repair hair oil

Rated 4.7 out of 5
Based on 416 reviews
Weightless oil that strengthens, repairs damage + reduces frizz View Molecular Repair Hair Oil product

PEPTIDE PREP™ detox shampoo

Rated 4.8 out of 5
Based on 258 reviews
Color-safe, non-stripping clarifying shampoo with the K18PEPTIDE™ View PEPTIDE PREP™ detox shampoo 8.5oz product

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.

20+ billion TikTok views 🔥 

*Disclaimers

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.
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healthier hair with every use
Reverse damage in 4 minutes with our breakthrough K18 molecular repair technology.

the K18 difference

Feel what’s possible with fewer steps, less waste + less time.
efficacy
patented K18PEPTIDE™ powers deeper + lasting repair.
simplicity
fewer steps for a streamlined routine.
speed
results in one 4-minute use.

how molecular repair compares

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.

feel what's possible with K18

See how K18 unlocks our community's expression
reviews
average rating 4.6 out of 5
Based on 7434 reviews
  • 5 Stars
    6082 Reviews
  • 4 Stars
    680 Reviews
  • 3 Stars
    305 Reviews
  • 2 Stars
    146 Reviews
  • 1 Star
    221 Reviews
92% of reviewers would recommend this product to a friend
Customer photos and videos
7434 Reviews
Reviewed by Teri
I recommend this product
Rated 5 out of 5
Review posted

5 Stars

This is a miracle for damaged hair……..

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K18Hair

We appreciate your review Teri!

Reviewed by Melissa S.
Verified Buyer
I recommend this product
Age
55 - 64
Hair Concern
  • Chemical damage
  • Color-care
  • Fragile/brittle hair
  • Dryness
  • Extending time between washes
Hair Type
  • Fine/Thin
My Results
  • Visible Difference
  • Less Breakage
  • Smoother Hair
  • Soft Touchable Hair
  • Cleaner, fresher hair
Rated 5 out of 5
Review posted

Want be without this ever!

I love this leave-in repair hair mask! This is so good that I will never let myself run out! I have been using this for several yrs and I love how it makes my hair so soft. My hair always feels and looks so much healthier! I love it!

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K18Hair

We appreciate your review Melissa!

Reviewed by Brittany W.
Verified Buyer
I recommend this product
Age
35 - 44
Client Hair Concerns
  • Chemical Damage
  • Heat Damage
  • Color Care
  • Dryness
Client Hair Types
  • Thick/Coarse
Client Results
  • Less Frizz
  • Stronger hair
  • Visible Difference
  • Smoother Hair
Rated 5 out of 5
Review posted

Repair Mask!!!!!

Clients and I are LOVING this repair mask!!!!!! Excited to contine using it!!!!

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K18Hair

Thank you for your review!

Reviewed by Lisa M.
Verified Buyer
I recommend this product
Age
45 - 54
Hair Concern
  • Chemical damage
  • Fragile/brittle hair
  • Dryness
  • Frizz
  • Heat damage
Hair Type
  • Curly/Coily
  • Thick/Coarse
My Results
  • Less Frizz
  • Visible Difference
  • Shinier Hair
  • Soft Touchable Hair
  • Smoother Hair
Rated 5 out of 5
Review posted

Silky Smooth!!

This product is AMAZING!!!! I am trying to repair my hair from a VERY BAD JAPANESE TREATMENT that went bad almost a year ago, not to mention he loss of hair 😩

I have used this product 3 times and my hair feels amazing…it’s shiny and soft. My natural hair is very curly and frizzy - as my hair starts to dry I can feel the softness happening….

Highly recommend

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K18Hair

Thank you Lisa for your review!

Reviewed by Mindy L.
Verified Reviewer
I recommend this product
Age
55 - 64
Hair Concern
  • Split-Ends
  • Color-care
  • Dryness
Hair Type
  • Straight/Wavy
  • Medium Density
  • Grey Hair
My Results
  • Visible Difference
  • Stronger Hair
  • Soft Touchable Hair
  • Shinier Hair
  • Smoother Hair
Rated 5 out of 5
Review posted

Best product EVER

I received a smaller size as a gift and wow it works I am over 60 and I color my hair and this product makes my hair so soft and smooth and takes the tangles out!

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K18Hair

We appreciate your review Mindy!

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