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
tile bestseller | color: black
4.9
Rated 4.9 out of 5 stars
2,142 Reviews

mini leave-in molecular repair hair mask

Mini retail size of our 4-minute leave-in treatment to reverse hair damage
Find a Distributor

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
460 Reviews
Weightless oil that strengthens, repairs damage + reduces frizz View Product
PEPTIDE PREP™ detox shampoo
4.9
Rated 4.9 out of 5 stars
284 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.
before after
before
after
"I have fallen in LOVE with this product and i haven’t had a single client disappointed"
-Sydne S.
before after
before
after
"I was so excited to try this stuff and then when I saw results instantly I knew I was in LOVE!!!"
- Shannon O.
before after
before
after
"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.
before after
before
after
"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.
before after
before
after
"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.
before after
before
after
"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.
before after
before
after
"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 ...

boost your salon’s bottom line with K18 at home

 Turn one-time treatments into ongoing success with K18's salon-to-retail strategy.

Biotech vs. traditional cosmetic chemistry

 Want real results? Choose biotech!
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 2,142 reviews
Write a Review (Opens in a new window)
2,142 reviews
  • Courtney
    Verified Reviewer
    Reviewing
    Full-Size Leave-In Molecular Repair Hair Mask 50 mL (WHOLESALE)
    I recommend this product
    Age 35 - 44
    Hair Concern Heat damage, Fragile/brittle hair, Dryness
    Hair Type Thick/Coarse, Straight/Wavy
    My Results Visible Difference, Stronger Hair, Less Breakage, Cleaner, fresher hair, Soft Touchable Hair
    Rated 5 out of 5 stars
    6 days ago
    Hair Transformation

    I started using this product over a year ago. My hair was brittle and breaking off like dog hair every day. My hair has transformed and the healthiest it’s ever been in my adult life. Follow the directions and don’t over is the product. I also use the heat protection from this line too when I chose to put heat to my hair and it’s made a difference too.

    Was this helpful?
    K18Hair PRO
    3 days ago

    Thank you so much, Courtney! We're absolutely thrilled to hear about your incredible hair transformation over the past year! It's amazing that your hair has gone from brittle and breaking to the healthiest it's ever been in your adult life - that's exactly what we love to hear! We're also so happy the heat protection from our line is working well for you too. Your advice about following directions and not overusing the product is spot on! Thanks for your wonderful 5-star review and for sharing your experience!

  • Brianna E.
    Verified Buyer
    Reviewing
    Full-Size Leave-In Molecular Repair Hair Mask 50 mL (WHOLESALE)
    I recommend this product
    Age 35 - 44
    Hair Concern Chemical damage, Heat damage, Dryness, Split-Ends, Frizz
    Hair Type Fine/Thin, Straight/Wavy
    My Results Less Frizz, Stronger Hair, Shinier Hair, Smoother Hair, Soft Touchable Hair
    Rated 5 out of 5 stars
    1 week ago
    This has transformed my hair

    I get bleach highlights every 6 weeks. I take really good care of my hair but there's only so much you can do when you bleach your hair. Ive been using this only 2 weeks and I got my hair done yesterday. My stylist was SO impressed with how healthy my hair is. She asked what I've been using and I told her! She told me she loves k18 as well!!

    Was this helpful?
    K18Hair PRO
    4 days ago

    Thank you so much for this incredible review, Brianna! We're absolutely thrilled to hear that the Leave-In Molecular Repair Hair Mask has transformed your hair in just 2 weeks! It's amazing that your stylist was so impressed with how healthy your hair looked, especially with regular bleaching every 6 weeks - that's exactly what we hoped to achieve with our molecular repair technology! We love that she's a K18 fan too and that you're experiencing such fantastic results even with frequent chemical processing. Your feedback about how it's helping maintain your hair's health despite the bleaching truly means the world to us, and we're so grateful to have you as part of our K18 community!

  • Danielle K.
    Verified Buyer
    Reviewing
    Full-Size Leave-In Molecular Repair Hair Mask 50 mL (WHOLESALE)
    I recommend this product
    Age 55 - 64
    Hair Concern Dryness, Fragile/brittle hair, Color-care
    Hair Type Medium Density, Straight/Wavy, Grey Hair
    My Results Less Frizz, Visible Difference, Smoother Hair, Soft Touchable Hair
    Rated 4 out of 5 stars
    1 month ago
    Super soft and great humidity control

    Just started using the K18 mask. I'm pleased at how soft my processed, menopausal hair is. It's become so dry, but K18 makes it feel and look more like hair again. I was really impressed with how well it controlled humidity induced frizz too - nothing I've tried before has worked so well against humidity.

    Was this helpful?
    K18Hair PRO
    3 weeks ago

    Thank you so much for this wonderful review, Danielle! We're absolutely thrilled to hear how much the K18 mask is transforming your processed hair and bringing it back to life. We're especially excited that you're seeing such impressive results with humidity control! That frizz-fighting power is something we're really proud of, and it sounds like it's making such a difference for you. Thank you for sharing your experience - it truly means the world to us! 💛

  • KanietSE K.
    Verified Buyer
    Reviewing
    Full-Size Leave-In Molecular Repair Hair Mask 50 mL (WHOLESALE)
    I recommend this product
    Age 25 - 34
    Hair Concern Chemical damage
    Hair Type Fine/Thin
    My Results Less Breakage
    Rated 4 out of 5 stars
    1 month ago
    After perm

    After an unsuccessful perm, I took this mask. As it is written in the instructions, I applied only it 6 times in a row. I'm glad that the smell of burning from my hair is almost gone. Visually, the changes are not as clear as I would like, but I will continue to use. I’m sure it would be better if I give more time

    Was this helpful?
    K18Hair PRO
    1 month ago

    Thank you so much for taking the time to share your experience with the Leave-In Molecular Repair Hair Mask after your perm situation, KanietSE! We're really glad to hear that you're already noticing the burning smell is almost gone — that's definitely a positive sign that the mask is working to repair the damage at a molecular level.

    We completely understand that visual changes can take time to become more apparent, especially after chemical damage from an unsuccessful perm. You're absolutely right that giving it more time will likely bring better results. The molecular repair process works progressively with each use, so continuing with the treatment as you're doing is exactly the right approach.

    We really appreciate your patience and persistence with the treatment, and we'd love to hear how your hair continues to improve as you keep using the mask. Your hair has been through a lot, so the fact that you're already seeing some positive changes is really encouraging!

  • Lillian D.
    Verified Buyer
    Reviewing
    Full-Size Leave-In Molecular Repair Hair Mask 50 mL (WHOLESALE)
    I recommend this product
    Age 18 - 24
    Hair Concern Heat damage, Fragile/brittle hair, Frizz, Split-Ends, Chemical damage
    Hair Type Curly/Coily, Straight/Wavy, Medium Density
    My Results Less Frizz, Defined Curl/Wave Pattern, Cleaner, fresher hair, Less Breakage, Visible Difference
    Rated 5 out of 5 stars
    1 month ago
    Good Progress So Far

    I have used this product a few times so far and have already seen great results and improvements. I’d like to keep up with it consistently and come back with update photos!

    Was this helpful?
    K18Hair PRO
    1 month ago

    Thank you so much for your incredible review, Lillian! We're absolutely thrilled to hear that our Full-Size Leave-In Molecular Repair Hair Mask is already delivering great results and improvements after just a few uses - there's no better compliment than knowing our molecular repair technology is working so beautifully that you're excited to keep up with it consistently! We'd love to see those update photos when you're ready to share your continued progress! ❤️