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mini size leave-in molecular repair hair mask 15mL
Mini Leave-In Molecular Repair Hair Mask 15 mL (WHOLESALE)
Before and after using k18 professional leave in hair mask and professional hair mist.
Before and after using k18 professional leave in hair mask and professional hair mist.
Before and after using k18 professional leave in hair mask and professional hair mist.
Before and after using k18 professional leave in hair mask and professional hair mist.
Biotech-powered K18PEPTIDE(TM) reverses hair damage in 4 minutes. Straight hair after bleach without K18and straight hair after bleach with K18.
highly concentrated formula = a little goes a long way
Before and after image using detox, mask, conditioner, and oil
full size leave in mask- start with 1 pump add more as needed. Mini size mask- start with 3 pumps add more as needed.
Clinically proven to reverse damage from: bleach + color, chemical services, and heat.
Mini Leave-In Molecular Repair Hair Mask 15 mL (WHOLESALE)
Mini Leave-In Molecular Repair Hair Mask 15 mL (WHOLESALE)
Where does K18 fit into your routine? 1. Shampoo (skip conditioner) 2. Towel dry 3. K18 4. wait for minutes 5. everything else
4.9
Rated 4.9 out of 5 stars
2,110 Reviews

mini leave-in molecular repair hair mask

Mini retail size of our 4-minute leave-in treatment to reverse hair damage
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Description

A retail-sized version of the K18 mask helps to maintain your client's hair strength and elasticity in-between salon appointments. This leave-in treatment mask for all hair types that reverses damage in 4 minutes. Patented peptide technology works to repair damage from bleach + color, chemical services, and heat* — restoring strength, softness, smoothness, and bounce to hair.

20+ billion TikTok views 🔥

*Disclaimers

Repairs Damage Caused By

  • Bleach + Color
  • Heat
  • Chemical Services
  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

Takes damage repair further – biomimetic peptide seamlessly fits in and reconnects 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 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 and with every service

  • 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, and heat*.

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

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

  • Vegan, color-safe, cruelty-free

  • DO clarify before K18 if your client is 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
  • 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

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
molecular repair hair oil
4.9
Rated 4.9 out of 5 stars
454 Reviews
Weightless oil that strengthens, repairs damage + reduces frizz View Product
PEPTIDE PREP™ detox shampoo
4.9
Rated 4.9 out of 5 stars
282 Reviews
Retail size of our color-safe, non-stripping clarifying shampoo formulated with the K18PEPTIDE™ View Product

Description

A retail-sized version of the K18 mask helps to maintain your client's hair strength and elasticity in-between salon appointments. This leave-in treatment mask for all hair types that reverses damage in 4 minutes. Patented peptide technology works to repair damage from bleach + color, chemical services, and heat* — restoring strength, softness, smoothness, and bounce to hair.

20+ billion TikTok views 🔥

*Disclaimers

got questions?
Get started here
K18 is engineered to work with every hair type, in every service, and with every routine.
Traditional conditioners leave a film on hair 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 styling product.
Water in damp hair swells the cuticle (the outside layer of hair) to open the gates for our biomimetic peptide to enter and travel to the innermost layers of hair. If the gates aren’t open, the product will stay on the surface—giving you mostly superficial repair. By applying on damp hair, you can use less, waste less, and still get the best results.
Think of the K18 mask as a highly concentrated treatment. It restores hair’s strength + elasticity in the innermost layers of hair, instead of traditional conditioners that coat the outside of hair. After the 4-minute wait time post-K18 mask, feel free to add a leave-in for a boost of conditioning if needed.
Yes, both formulas are the same. The PRO mask is conveniently sized for PRO use.
soft, strong, bouncy hair for everyone
Repair damage for hair like new* in 4 minutes.
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"I have fallen in LOVE with this product and i haven’t had a single client disappointed"
-Sydne S.
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"I was so excited to try this stuff and then when I saw results instantly I knew I was in LOVE!!!"
- Shannon O.
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"Hands down the best product I’ve used to repair damaged hair. I live by this product and my clients love it too!"
- Nicole C.
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"This product is a game changer, especially for blondes! I have seen some of the most damaged hair become like new again! It’s a miracle! Ty K18!"
- Lacey P.
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"I absolutely love this product on my clients and myself!!! As a hairdresser, I’ve tried all those bond builders and what not and yes they are great but what sets k-18 apart from these other bond builders is that the technology behind it really goes deep into the hair. I have had many of my clients who had so many compliments about how healthy their hair looks and feels."
- Justina M.
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"This stuff stomps the yard! I cannot even fathom coloring or lightening hair, without K18. It’s in my prices and no one complains because their hair feels and looks amazing. The client below tried at home lightening and came in to have it fixed."
- Ryan H.
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"I’m currently in cosmetology school so of course all my family and friends want me to do their hair! Ive started using K18 on anyone i have to bleach and its like a little miracle!"
- Nicole M.
powered by K18PEPTIDE™

Biomimetic peptide clicks into hair’s keratin structure—the source of core strength—for soft, shiny, bouncy results that won’t wash away.

learn more
how to use K18
lightener / color
1. Section dry hair into 4 quadrants.

2. Apply a minimum of 10 full sprays of K18 professional molecular repair hair mist to each quadrant, increasing up to 20 sprays per quadrant as needed, depending on client’s length, density, or level of damage.

3. Wait 4 minutes (do not rinse out).

4. If needed, dry the hair prior to applying lightener or color. Then perform your desired technique.

5. Process your lightener or color as usual, then rinse and shampoo with K18 PEPTIDE PREP™ detox shampoo. Do not condition.

6. Apply 1-3 pumps of K18 professional molecular repair hair mask based on your client’s length and density, starting at the ends and working up towards the roots.

7. Wait 4 minutes (do not rinse), then apply 1-3 drops of K18 molecular repair hair oil to mid-lengths and ends.

8. Wait 4 minutes, then proceed with cut or style as usual.

9. Add an additional 1-3 drops of K18 molecular repair hair oil to dry hair as a finisher.

Please see the “K18 + toning or glossing” section for more information on toning with K18.
learn more on our blog

The Top K18 Mask FAQs

 answering your most-asked questions.

How much leave-in mask should you use?

 A handy dosage guide for every hair type, density, and length.

How to Build Your Clients’ Take-Home Routines with K18 Mask + DAMAGE SHIELD

 A PRO’s top tips for building your clients’ take-home routines

Can You Air Dry Without Frizz?

 How to get the smoothest results possible, whatever the forecast.  

K18 FUNdamentals 02: Masks + Conditioners vs. K18

 You know what's fun? When your product works. We'll be breaking down key info + recommendations weekly to help you get the most out of K18   We’re ...

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feel what's possible with K18
See how K18 unlocks our community's expression
4.9
Rated 4.9 out of 5 stars
Based on 2,110 reviews
Write a Review (Opens in a new window)
2,110 reviews
  • Nancy J.
    Verified Buyer
    Reviewing
    Full-Size Leave-In Molecular Repair Hair Mask 50 mL (WHOLESALE)
    I recommend this product
    Age 45 - 54
    Hair Concern Chemical damage
    Hair Type Curly/Coily
    My Results Less Breakage, Bouncy Hair
    Rated 5 out of 5 stars
    21 hours ago
    Love this hair mask

    This mask has saved my hair!

    Was this helpful?
    K18Hair PRO
    3 minutes ago

    Thank you so much for your incredible review, Nancy! We're absolutely thrilled to hear that our Full-Size Leave-In Molecular Repair Hair Mask has saved your hair - there's no better compliment than knowing our molecular repair technology is giving your hair the rescue it needed! ❤️

  • Sadie M. G.
    Verified Buyer
    Reviewing
    Full-Size Leave-In Molecular Repair Hair Mask 50 mL (WHOLESALE)
    I recommend this product
    Age 45 - 54
    Hair Concern Chemical damage, Heat damage, Color-care, Frizz, Split-Ends
    Hair Type Thick/Coarse
    My Results Less Frizz, Visible Difference, Stronger Hair, Less Breakage, Smoother Hair
    Rated 5 out of 5 stars
    2 days ago
    Omg this treatment is Amazing!

    I have tried all kind of hair treatments but this one is the best on the market. Kinda expensive but you get excellent results so worth it.

    Was this helpful?
    K18Hair PRO
    23 hours ago

    Thank you so much for your incredible review, Sadie! We're absolutely thrilled to hear that our Full-Size Leave-In Molecular Repair Hair Mask stands out as the best treatment you've tried after testing so many different options - there's no better compliment than knowing our molecular repair technology is delivering such excellent results that make the investment truly worth it for you! ❤️

  • Mark T.
    Verified Buyer
    Reviewing
    Full-Size Leave-In Molecular Repair Hair Mask 50 mL (WHOLESALE)
    I recommend this product
    Age 18 - 24
    Hair Concern Chemical damage, Fragile/brittle hair, Frizz, Split-Ends
    Hair Type Fine/Thin, Medium Density
    My Results Soft Touchable Hair, Smoother Hair, Less Frizz, Visible Difference
    Rated 5 out of 5 stars
    5 days ago
    Great Results for chemical damage

    After using the K18 repair mask, I noticed my hair was a lot less frizz, felt noticeably stronger and less prone to breakage. I truly love the results i get from this product and I hope to use it in my routine.

    Was this helpful?
    K18Hair PRO
    5 days ago

    Thank you so much for your incredible review, Mark! We're absolutely thrilled to hear that our Full-Size Leave-In Molecular Repair Hair Mask is delivering such amazing results for your chemical damage - there's no better compliment than knowing our molecular repair technology is making your hair less frizzy, noticeably stronger, and less prone to breakage! We love that you're seeing such transformative results and hope it becomes a staple in your routine. ❤️

  • Emily R. U.
    Verified Buyer
    Reviewing
    Full-Size Leave-In Molecular Repair Hair Mask 50 mL (WHOLESALE)
    I recommend this product
    Age 25 - 34
    Hair Concern Heat damage, Frizz, Dryness
    Hair Type Curly/Coily, Thick/Coarse
    My Results Defined Curl/Wave Pattern, Less Frizz, Less Breakage, Visible Difference, Stronger Hair
    Rated 5 out of 5 stars
    2 weeks ago
    50 ML OF GOLD

    After 20 years of heat damage and breakage, I’ve spent the last year trying to revive my natural curls and this product IS DOING MIRACLES. After just a few uses and a couple of trims, my curl pattern started coming back with more structure, shine, and LIFE. I’m already on my second bottle. (1st pic: Sept-25; 2nd pic: Jan-26)

    Was this helpful?
    K18Hair PRO
    2 weeks ago

    Thank you so much for your incredible review, Emily! We're absolutely thrilled to hear that our Full-Size Leave-In Molecular Repair Hair Mask is doing miracles for your natural curls- there's no better compliment than knowing our molecular repair technology is bringing back your curl pattern with such amazing structure, shine, and life! ❤️

  • Sarah M.
    Verified Buyer
    Reviewing
    Full-Size Leave-In Molecular Repair Hair Mask 50 mL (WHOLESALE)
    I recommend this product
    Age 45 - 54
    Hair Concern Heat damage, Chemical damage, Dryness, Frizz, Fragile/brittle hair
    Hair Type Grey Hair, Straight/Wavy
    My Results Less Frizz, Visible Difference, Defined Curl/Wave Pattern
    Rated 5 out of 5 stars
    1 month ago
    Miracle worker!

    I have struggled with my damaged hair and undefined curls for YEARS. I've tried every mask under the sun. K18 has worked a miracle on my hair. I'm 6 applications in and I have been able to wear my hair curly without half a ton of gel. I can't wait to see the progress in a month or 2!

    Was this helpful?
    K18Hair PRO
    1 month ago

    Thank you so much for your incredible review, Sarah! We're absolutely thrilled to hear that our molecular repair technology is working miracles on your damaged hair and undefined curls - there's no better compliment than knowing you can finally wear your curls naturally without needing half a ton of gel! It's so exciting that you're already seeing such amazing results after just 6 applications, and we can't wait for you to experience even more transformation in the coming months! ❤️