mini leave-in molecular repair hair mask
4-minute leave-in treatment to reverse hair damage
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.
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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.
Repair damage for hair like new* in 4 minutes.
1. Shampoo, do not condition. Towel-dry thoroughly.
2. Apply 1-3 pumps 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 styling product + style as usual. Use for 4-6 washes, then as needed.
*k18hair.com/disclaimers
See how K18 unlocks our community's expression
- Effectiveness
- Texture
- Repair
- Appearance
- Value
- Wendy M.Verified BuyerReviewingJumbo Leave-In Molecular Repair Hair Mask 100mLI recommend this productAge 55 - 64Hair Concern Fragile/brittle hair, Dryness, Split-EndsHair Type Thick/Coarse, Grey HairMy Results Visible Difference, Less Breakage, Stronger Hair, Smoother Hair, Soft Touchable HairRated 5 out of 5 stars1 hour agoWow Power
When nothing else works K18 is.
I had almost given up on my hair. I spent years buying products that promised miracles but delivered disappointment. Then I found K18.
This isn’t just another conditioner or mask—it’s molecular hair repair that reaches deeper than anything I’ve ever tried. When nothing else worked, K18 did. My hair feels stronger, healthier, softer, and looks alive again.
If your hair has been damaged by bleach, color, heat, or years of wear and tear, don’t lose hope. K18 gave me results I honestly didn’t think were possible. It’s one of the few products that truly lives up to the hype.
KK18Hair4 minutes agoThank you so much for your review, Wendy! 💛 We're thrilled to hear the Jumbo Leave-In Molecular Repair Hair Mask has transformed your hair. Your support means everything to us, and we're grateful you're part of the K18 community! ✨
- Ashley W.Verified BuyerReviewingJumbo Leave-In Molecular Repair Hair Mask 100mLI recommend this productAge 35 - 44Hair Concern Chemical damage, Heat damage, Color-care, Frizz, Fragile/brittle hairHair Type Thick/Coarse, Straight/Wavy, Curly/CoilyMy Results Less Frizz, Visible Difference, Stronger Hair, Less Breakage, Smoother HairRated 5 out of 5 stars3 hours agoSo soft!
I absolutely love this product! It makes my hair feel so soft and look so healthy. No more crazy breakage, split ends, or fly aways. It is so easy to use too!
KK18Hair3 hours agoThank you so much for your wonderful review, Ashley! We're thrilled to hear that the Jumbo Leave-In Molecular Repair Hair Mask is making such a difference for your hair. Your kind words about the softness and how it's helping with breakage, split ends, and frizz mean a lot to us. We're so glad you're finding it easy to use too! Thank you for sharing your experience and for being part of the K18 community!
- Deb M.Verified BuyerReviewingFull-Size Leave-In Molecular Repair Hair Mask 50mLI recommend this productAge 45 - 54Hair Concern Chemical damage, Heat damage, Color-care, Dryness, Split-EndsHair Type Fine/ThinMy Results Less Frizz, Smoother HairRated 5 out of 5 starsYesterdayMagical!
Love everything about this product
KK18HairYesterdayThank you so much for your amazing review! 💛 We're thrilled to hear you're loving our Full-Size Leave-In Molecular Repair Hair Mask. Your support means the world to us! ✨
- Kari A. B.Verified BuyerReviewingMini Leave-In Molecular Repair Hair Mask 15 mLI recommend this productAge 45 - 54Hair Concern Chemical damage, Frizz, Color-care, Fragile/brittle hair, DrynessHair Type Medium Density, Straight/WavyMy Results Less Frizz, Visible Difference, Stronger Hair, Defined Curl/Wave Pattern, Soft Touchable HairRated 5 out of 5 stars2 days agoIt works great.
This worked so well in my hair. I have bleached and semi permanent hair color. I have damaged my hair from bleaching it so much. That this has made my hair feel and
Look alot more healthier. Buying a bigger bottle this week.
KK18Hair2 days agoThank you so much for your amazing review! 💛 We're thrilled to hear our Mini Mask is helping restore your hair's health and appearance. Your support means the world to us! ✨
- Elvira L.Verified ReviewerReviewingMini Leave-In Molecular Repair Hair Mask 15 mLI recommend this productAge Under 18Hair Concern Fragile/brittle hair, Heat damage, Oily hair/scalp, Split-Ends, FrizzHair Type Medium DensityMy Results Less Frizz, Bouncy Hair, Visible Difference, Stronger Hair, Less BreakageRated 5 out of 5 stars3 days agoSaved my hair
I’ve been on the hunt for a leave-in hair product that doesn’t weigh my hair down or leave it looking greasy. My hair is very brittle and has never been able to grow past a certain length.
I’ve been using this for over a month now, and my hair feels so much stronger. I notice way fewer split ends than I used to, and my hair is shinier and softer. Out of all the leave-in products I’ve tried, this is the only one that doesn’t weigh my hair down or irritate my scalp. I’m genuinely impressed and will definitely keep repurchasing it.
KK18Hair3 days agoThank you so much for your amazing review, Elvira! 💛 We're thrilled to hear our Mini Leave-In Mask has transformed your hair. Here's to continued strength and growth! ✨