Product Overview

K18 Leave-In Molecular Repair Hair Mask is a patented peptide hair mask to reverse damage from hair treatments.

In just four minutes, this professional, salon-grade hair treatment from K18 Biomimetic Hairscience heals damage from bleach, color treatments, styling heat and chemical services. Formulated with a first of it's kind, patented oligopeptide, also known as K18Peptide™, this bioactive treatment reduces split ends, breakage and color fade, while restoring elasticity, bounce, softness and strength. Unlike conditioning treatments that hydrate the outer layer of hair and bonding treatments that wash out over time, this K18 hair product actually heals hair from the inside out and produces results that won't wash away.

Key Features:

K18Peptide™, a unique patented peptide molecule, repairs broken keratin chains that make up the building blocks of hair
Heals damage from bleach, color, chemical services, heat, and mechanical styling
pH balance of 5.0-6.0
Doesn't wash away with shampoo, leaving lasting results
Vegan, color-safe and cruelty-free
Ideal for all hair types

Restore bounce, elasticity and hydration to damaged hair with K18 Leave-In Molecular Repair Hair Mask.

Highlights

Heals hair damage with K18Peptide™
Ideal after bleaching and chemical services
Unique, no-rinse treatment

Ingredients

Directions

Shipping & Returns

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Questions & Answers (3)

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Product Specifications

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About the Brand

Featured In

Customer Reviews (474)

Overall Rating

4.4

Based on 474 reviews

Review Summary

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HarmonyZ

Verified Purchase

March 04, 2024

Doesn’t make thin hair greasy

I used this product according to the label and it’s working great. I have fine/thin hair and it’s not weighed down at all. I use 1 to 2 pumps each time I use it. I can see less breakage where I wear my hair tie.

LovelySkin Customer

Verified Purchase

February 27, 2024

One of The Best Products for Damaged Hair

k18 is one of the best products in the market for damaged hair. If you have highlighted, double processed or heat styled hair, you need this product. Make sure to apply it on towel dry hair, not to use conditioner prior, and to wait the indicated time prior to proceeding with other products or styling. This doesn't replace protein treatments, other bond repair products or serums. K18 works in a totally different way to heal damaged hair and makes a great addition to your monthly hair routine.

LovelySkin Customer

Verified Purchase

February 01, 2024

Happy!

After following instructions I am now down to maintenance treatments. I do notice a difference in my hair after using product. I do follow with conditioner and am happy with the results.

Skinlove

Verified Purchase

January 31, 2024

Ease of Application

I like this product when I'm in a time crunch - I don't have to apply conditioner (in fact you aren't supposed to) and then I apply this. There is no waiting or applying to damp hair before showering that some other products require. It hasn't been life changing in terms of impact to my hair but my hair is relatively healthy but the ease of application is superb.

LovelySkin Customer

Verified Purchase

January 03, 2024

Love

I have dry and damaged hair, this product is making me like my poor hair again.

Hurley

Verified Purchase

December 01, 2023

LOVE

This is the only hair repair treatment I’ve used that I’ve actually seen and felt a difference in my hair. Wish it came in a bigger size than 1.7 oz though.

Zippy123

Verified Purchase

November 24, 2023

No Stars Should Be An Option

Hate it. Did damage to my hair, I saw zero improvement and more damage. I gave it away and returned to a less expensive brand which I never should have strayed from.

LovelySkin Customer

Verified Purchase

November 20, 2023

Great treatment, but can't tell if it's working

My hair did feel stronger after going through a whole bottle, but I'm not sure it really repaired my hair. That being said, I have virgin hair (hasn't ever been colored), and I don't heat style my hair. It's a great gift I think.

Fanchera

Verified Purchase

November 09, 2023

Worth it

I started using this a little over a year ago. I use it once a week and it lasts me about 3 months. I have long hair and I’ve noticed a lot less breakage which has allowed me to go longer between hair trimming. I’m 48 and my hair hasn’t been this long since I was 26! Highly recommend!

LovelySkin Customer

Verified Purchase

September 25, 2023

So worth the price

I purchased this product about 6 months ago, and I still have product left. I have incredibly long hair, and I use the product as directed and it has lasted so long. I have noticed an improvement in the breakage and frizziness of my hair and plan to continue using!

Mmm11y

Verified Purchase

September 06, 2023

Good Product

I do like this hair mask. But it does require about 9 pumps of it. It says to start out with 3 but thats definitely not enough. Especially after not using conditioner in the shower. It’s rough on the hair when you are putting it on but I do see a difference in using it.

EmilyIm

Verified Purchase

August 12, 2023

best treatment help hair

this is the best product for hair i used to use many product for hair but this is really repair my hair and easy to use i really love it and worth to try

LovelySkin Customer

Verified Purchase

August 06, 2023

Must have for damaged hair

My highlighted hair is frizzy and prone to split ends. My stylist recommended this product to me as she uses the system in her salon. My hair feels stronger and softer after using this.

lss

Verified Purchase

June 22, 2023

Not worth it

Itty bitty bottle. Very expensive. Didn't do a darn thing despite all the promises. I have had far better results with other hair masques at much lower prices and greater volume

Joolee

Verified Purchase

June 20, 2023

Used bottle fast

My hair is wavy and dry, let’s start there. I have to use a leave-in conditioner for it to be manageable. That being said, I needed to use several pumps per treatment in order to comb through. The bottle didn’t last long. However, maybe what I need to do is work this in and then go with my regular leave-in. Regardless, it did make my hair smoother, shinier, and the ends looked cleaner. I will purchase again.

LovelySkinLIzS

Verified Purchase

June 03, 2023

Love this treatment

This has helped restore my color damaged hair. I like that it is a leave in treatment and you just have to wait four minutes before styling as normal. I got a sample and liked the product so much I bought a full sized bottle.

LovelySkin Customer

Verified Purchase

June 01, 2023

love this stuff, just wish it wasn't so expensive

I can't believe how amazing this stuff is. It has been a complete game changer for my hair. only reason I am giving it 4 stars instead of 5 is because of the price

Alaska87

Verified Purchase

May 12, 2023

Yeah it works

Don’t know how it’s any different from olaplex or any other hair repair treatment. I like it but it’s too expensive to repurchase.

Federika

Verified Purchase

May 07, 2023

Amazing!

I recently heard about K18 from a friend who obsesses about her hair and researches hair care products. I have had great results using a competitor brand product, but I read that the two different brand products can be used in combination to achieve the different benefits of each brand's formula. I ordered the small size bottle to give this a try. I shampoo my hair every 4-5 days, and so far I have used this after three hair washes. It is pretty amazing to see the results. I usually don't like "leave-in" products, but this product does not weigh my hair down at all. My hair looks shiny, less frizz, and there is no loss of body after using it. The manufacturer recommends using it after 4-5 washes and then on an as-needed basis after that. This will definitely be a staple for periodic use in my haircare routine. Highly recommend!

LovelySkin Customer

Verified Purchase

April 08, 2023

I'm still on the fence...

Background on my hair- It's very fine and dark, and I've been getting balayage for a few years now to lighten it significantly. Obviously the bleach has taken a toll because I have a lot of breakage! Trying out K18, I immediately noticed it gave my hair a softness and shine that it was missing. BUT I'm not actually sure if it's helping to reduce breakage! I think Olaplex #3 helps reduce my breakage more than this product unfortunately.

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K18 Leave-In Molecular Repair Hair Mask

Product Overview

K18 Leave-In Molecular Repair Hair Mask is a patented peptide hair mask to reverse damage from hair treatments.

Highlights

Ingredients

Directions

Shipping & Returns

Questions & Answers (3)

Product Specifications

Special Offers

About the Brand

Featured In

Customer Reviews (474)

Overall Rating

Review Summary

Write a Review

Doesn’t make thin hair greasy

One of The Best Products for Damaged Hair

Happy!

Ease of Application

Love

LOVE

No Stars Should Be An Option

Great treatment, but can't tell if it's working

Worth it

So worth the price

Good Product

best treatment help hair

Must have for damaged hair

Not worth it

Used bottle fast

Love this treatment

love this stuff, just wish it wasn't so expensive

Yeah it works

Amazing!

I'm still on the fence...

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