K18 Leave-in Molecular Repair Hair Mask, 1.7 fl. oz.

|14 ratings
Item # 990457205
Current price is Now $39.92
was $49.98
$10.06 off
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Columbus, 43215
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Highlights

  • Leave-in hair treatment mask
  • Rebuilds hair from the inside out
  • Proven to reverse hair damage in 4 minutes
  • Leave-in formula provides lasting results
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k18 leave-in molecular repair hair mask, 1.7 fl. oz. Front-facing white 50 ml/1.7 fl. oz. pump bottle labeled K18 Biomimetic Hairscience beside its white-and-orange retail box displaying "leave-in molecular repair hair mask" in English and French; studio background, matte finish bottle, often carried as a travel-size leave-in treatment.
K18 Leave-in Molecular Repair Hair Mask, 1.7 fl. oz.
Hero image 0 of K18 Leave-in Molecular Repair Hair Mask, 1.7 fl. oz., 0 of 4

About this item

Product details

In just four minutes, the K18 Leave-in Molecular Repair Hair Mask reverses hair damage on a molecular level. K18 PEPTIDE has been proven to repair bleach and color damage, as well as chemical services and heat. It provides immediate and lasting results that restore hair strength, softness, smoothness, and bounce.

Renews Hair Strength and Elasticity

This hair mask is designed to provide smooth, bouncy hair by renewing its core strength and elasticity at the innermost layer. With its unique K18 PEPTIDE formula, this hair mask not only repairs bleach and color damage but also combats the effects of chemical services and heat exposure.

Hair Mask Starts Repairing Your Hair Immediately

The K18 Leave-in Molecular Repair Hair Mask starts repairing your hair immediately and lasts beyond your next wash, ensuring ongoing reparative results.

Suitable for All Hair Types

This hair mask is suitable for all hair types, as it works on a molecular level where all hair is the same. Whether you have straight, wavy, curly, or coily hair, the K18 Leave-in Molecular Repair Hair Mask helps to improve hair quality and texture.

Disclaimer: Sam’s Club is committed to offering quality products and services at an exceptional value. To serve this goal, these products were not purchased directly from the manufacturer or its authorized distributor but from a third-party dealer with strict controls to verify authenticity and quality. Some manufacturers limit or exclude their warranties on these products. However, these items remain fully covered by Sam’s Club’s 100% Merchandise Satisfaction Guarantee. If you are not satisfied with your purchase for any reason, return your item and we'll replace it or provide a refund.

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Specifications

  • Vegan
  • Cruelty-free
  • Color-safe

Member ratings & reviews

4.1 out of 5 stars
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14 ratings14 reviews
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Showing 1-3 of 14 reviews

Jul 6, 2026
Reviewer name: Diane
5 out of 5 stars
5 out of 5 stars review

Lives up to the hype.

I absolutely love K18. My hair has been damaged for so long and so frizzy. I decided to try K18. I didn't have much hope. I noticed a huge difference with the first use. My hair afterwards was so soft and frizz free. My 2nd use, even better! The improvement in my hair is amazing! I'll be repurchasing again. BTW, the K18 is 100% authentic!

Helpful?6VDXC18GH1GI15995073092
Sep 1, 2026
Reviewer name: anonymous
5 out of 5 stars
5 out of 5 stars review

I was skeptical…

But I am so glad I gave it a shot. This may be the first product that seems to legitimately repair my hair. My breakages, split ends, etc., are way down. My hair feels fuller and looks healthier. The cream itself isn’t greasy or heavy and seems to go a long way. I’ll be buying this again for sure.

Helpful?6VDXC18GH1GI15995073092
Aug 27, 2026
Reviewer name: anonymous
5 out of 5 stars
5 out of 5 stars review

Worth It!

Absolutely love K18 for my bleached blonde hair! It leaves my hair noticeably softer, stronger, shinier, and much less brittle without weighing it down. A little goes a long way, and my hair genuinely feels healthier after using it. Worth it!

Helpful?6VDXC18GH1GI15995073092