---
product_id: 365126853
title: "K18 Biomimetic Hairscience Leave-In Molecular Repair Hair Mask, 5 ml"
brand: "k18"
price: "FREE"
currency: JPY
in_stock: false
reviews_count: 13
url: https://www.desertcart.jp/products/365126853-k18-biomimetic-hairscience-leave-in-molecular-repair-hair-mask-5
store_origin: JP
region: Japan
---

# 4-minute fast repair Patented K18Peptide tech Lasting, non-wash effect K18 Biomimetic Hairscience Leave-In Molecular Repair Hair Mask, 5 ml

**Brand:** k18
**Price:** FREE
**Availability:** ❌ Out of Stock

## Summary

> 🧪 Unlock your hair’s molecular magic in minutes!

## Quick Answers

- **What is this?** K18 Biomimetic Hairscience Leave-In Molecular Repair Hair Mask, 5 ml by k18
- **How much does it cost?** FREE with free shipping
- **Is it available?** Currently out of stock
- **Where can I buy it?** [www.desertcart.jp](https://www.desertcart.jp/products/365126853-k18-biomimetic-hairscience-leave-in-molecular-repair-hair-mask-5)

## Best For

- k18 enthusiasts

## Why This Product

- Trusted k18 brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Rapid 4-Minute Repair:** Clinically proven to reverse hair damage in just 4 minutes—because your time is precious.
- • **Leave-In, Not Washed Out:** Unlike traditional masks, results last beyond shampooing for ongoing transformation.
- • **Molecular-Level Rejuvenation:** Patented K18Peptide penetrates deep to reconnect broken hair chains for strength and elasticity.
- • **All Hair Types, All Expressions:** Works on every hair type and damage level—because your hair deserves a fresh start.
- • **Vegan & Cruelty-Free Confidence:** Ethically crafted formula that’s safe for color-treated hair and your values.

## Overview

K18 Biomimetic Hairscience Leave-In Molecular Repair Hair Mask is a revolutionary 5ml treatment that repairs extreme hair damage from bleach, color, chemical services, and heat in just 4 minutes. Powered by a patented peptide technology, it penetrates deep to reconnect broken keratin chains, restoring up to 91% of original strength and 94% elasticity. Suitable for all hair types, this vegan, cruelty-free formula delivers lasting results that don’t wash away, making it the ultimate at-home solution for professional-grade hair renewal.

## Description

Product Description K18 is a leave-in treatment mask for all hair types that clinically reverses damage in 4 minutes. The patented peptide technology works to repair damage from bleach, color, chemical services & heat – restoring strength, softness, smoothness, and bounce to hair. Our K18Peptide™ is clinically proven to reverse damage in just 4 minutes. Heals damage from bleach, color, chemical services, and heat Restores strength, softness, smoothness, and bounce Doesn’t wash away with shampoo, leaving lasting results Vegan, color-safe, cruelty-free up to 91% original strength* up to 94% original elasticity* * Results observed in a clinical study while using mist and mask as part of a bleaching treatment. Results may vary depending on hair type, quality and history. DO use a clarifying shampoo if you’re a heavy product or dry shampoo user to remove buildup and help our peptide penetrate and get where it needs to go. DO wait the full 4 minutes before styling or applying other product DO use every 4-6 shampoos consecutively to see and feel ongoing results How to Use K18: IN the shower 1 - Shampoo, do not condition. OUT of the shower 1 - Towel dry thoroughly. 2 - Begin with 1 pump of the K18 Mask and add more as needed depending on the length, thickness, and condition. 3 - Work evenly into hair from ends to roots, one pump at a time. 4 - Let sit for 4 minutes to activate. 5 - Do NOT rinse out. 6 - Style as usual. Ingredients 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. Directions IN the shower: Shampoo, do not condition. OUT of the shower: Towel dry thoroughly. Begin with 1 pump of the K18 Mask and add more as needed depending on the length, thickness, and condition. Work evenly into hair from ends to roots, one pump at a time. Let sit for 4 minutes to activate. Do NOT rinse out. Style as usual. Safety Warning K18 Biomimetic Hairscience Leave-In Molecular Repair Hair Mask, 5 ml

Review: Game changer - I don't normally write reviews unless I'm absolutely blown away. I saw a couple of negative reviews on here but I purchased anyway after watching some videos on YouTube and I wasn't disappointed. A few days ago I went from brown to blonde at home. As you can see in the picture to the left (and that's before I processed it again with a toner) as you can see there's damage...I knew there would be going back to blonde. The picture to the left is 2 days ago. This morning I shampooed my hair twice with a clarifying shampoo, it's important to really shampoo and to NOT put any conditioner on. Towel dry. .. always gently squeeze the water from the hair with the towel,never rub the hair with a towel when drying. I understand some people will find it hard to not condition but if u stand up in the shower when washing it and dry your hair this way your hair shouldn't be tooo tangly, when you have removed as much excess water as you can apply a SMALL amount... the package has a guideline for the length of hair. I used a pea sized amount and I did think it couldn't possibly be enough but TRUST THE PROCESS! I combed through and left it on probably 10 mins (it says atleast 4 minutes) do not wash it out , after the initial 4 mins you can add styling products, I used a conditioning and heat protecting spray before blow drying. I can't get over how good my hair feels after 1 use, it feels better then pre bleaching, I honestly can't wait to wash my hair again! I will be buying the full size bottle, yes it's expensive but it's insurance for your hair. Its just over 50 pounds on their site for 50mls... that's like a pound per ml and I think i will use 1 ml per use... that's 50 uses for my length hair. I never had results like this with olaplex! I definitely recommend you try the sample size, follow the instructions and you will get a couple of uses...I think I will have 4 uses. This has to be one of the best things I've brought!
Review: Improved hair health and appearance - I bought the 5ml sample size which was perfect - though it looks tiny it has lasted six applications for my shoulder-blade length, medium thickness, bleach damaged, heat-treated, perimenopausal hair. I had noticed a lot of breakage, especially near my crown. My hair always felt frazzled at the ends and just didn't look shiny or healthy. I used Head and Shoulders clarifying shampoo then K18 for six consecutive washes, followed by Redken Extreme Length leave in conditioner. You have to wait four minutes once you've applied the K18 then style as usual (no need to wash out). It's simple to use in the shower routine and adds no extra time - in fact it saves time as you don't need to use conditioner afterwards. My hair felt softer and healthier after each use and others have complimented my hair. It's not got any particular wow factor after one wash but my hair is now 100% in better condition. Broken ends are smoother and less noticeable, my hair looks so much shinier, fuller and healthier. I'll have a rest from this now but probably do another six washes after my next lightening session to maintain strength and health.

## Features

- K18 Leave-In Repair Hair Mask Treatment to Repair Dry or Damaged Hair - 4 Minutes to Reverse Hair Damage from Bleach, Color, Chemical Services and Heat
- An At-home Leave-In Treatment infused with the patented K18Peptide that renews hair to its most youthful, healthy state. Benefits: Works to repair even the most extreme damage caused by bleach and color, chemical services, and heat.
- Creates Like Hair Like New: Traveling into the inner-most layers of hair to reach the core polypeptide chains our revolutionary K18Peptide is just the right size and makeup to reconnect broken chains responsible for hair strength and elasticity.
- Renews All Hair Types: K18 doesn’t just hide damage or patch it up leaving hair brittle, it transforms even the most extreme damage into hair that looks and feels like new. K18 works on all hair types, all generations, all types of expression.
- Lasting Results That Won't Wash Away: The K18Peptide mimics the natural building blocks of hair and therefore is recognized as natural—so it’s able to integrate itself with the keratin chains to rebuild and restore hair immediately and over time.

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B08VD75V4F |
| Additives | Vegan |
| Age Range Description | Adult |
| Age range (description) | Adult |
| Benefits | Breakage Control, Damage Control, Renews Hair Cell, Split Ends Repair, Strengthening |
| Best Sellers Rank | 66,905 in Beauty ( See Top 100 in Beauty ) 244 in Hair Masks |
| Brand | K18 |
| Brand Name | K18 |
| Customer Reviews | 4.2 out of 5 stars 3,725 Reviews |
| Global Trade Identification Number | 00858511001098 |
| Hair Conditioner Type | Leave-In Hair Conditioner |
| Hair Type | Damaged |
| Hair type | Damaged |
| Item Dimensions | 10 x 10 x 10 centimetres |
| Item Form | Cream |
| Item Weight | 5 Milligrams |
| Item form | Cream |
| Liquid Volume | 5 Millilitres |
| Manufacturer | K18 |
| Manufacturer Part Number | 858511001081_SML |
| Material Features | Vegan |
| Material Type Free | Materials of animal origin |
| Material feature | Vegan |
| Model Number | K18-31001 |
| Number of Items | 1 |
| Package Type Name | Tube |
| Product benefits | Breakage Control, Damage Control, Renews Hair Cell, Split Ends Repair, Strengthening |
| Recommended Uses For Product | Repair Damaged Hair |
| Scent Name | Fresh |
| Size | 1 g (Pack of 1) |
| Special Features | Not Tested On Animals |
| UPC | 858511001081 858511001098 |
| Unit Count | 1.0 gram |

## Product Details

- **Brand:** K18
- **Hair type:** Damaged
- **Item form:** Cream
- **Material feature:** Vegan
- **Product benefits:** Breakage Control, Damage Control, Renews Hair Cell, Split Ends Repair, Strengthening

## Images

![K18 Biomimetic Hairscience Leave-In Molecular Repair Hair Mask, 5 ml - Image 1](https://m.media-amazon.com/images/I/71M1X--Z2hS.jpg)
![K18 Biomimetic Hairscience Leave-In Molecular Repair Hair Mask, 5 ml - Image 2](https://m.media-amazon.com/images/I/61K6KSN+LZL.jpg)
![K18 Biomimetic Hairscience Leave-In Molecular Repair Hair Mask, 5 ml - Image 3](https://m.media-amazon.com/images/I/81YZVqn0AML.jpg)
![K18 Biomimetic Hairscience Leave-In Molecular Repair Hair Mask, 5 ml - Image 4](https://m.media-amazon.com/images/I/61jy4AYgOrL.jpg)
![K18 Biomimetic Hairscience Leave-In Molecular Repair Hair Mask, 5 ml - Image 5](https://m.media-amazon.com/images/I/61eNUjWIhPS.jpg)

## Available Options

This product comes in different **Size** options.

## Questions & Answers

**Q: Hi folks do you put this on to dry hair or damp hair? Thank you 😊**
A: You shampoo and towel dry your hair, a clarifying shampoo if you have (do not use conditioner). Then apply 1-5ml depending on hair length, working into more damaged areas mid lengths and ends, comb through. Leave for 4 minutes and then style as usual (you can then add all your usual styling products). Hope this explains. Thanks TheHairShop

**Q: I'd like to know the cost to the UK - don't understand the tax and import implications but don't want any surprises!**
A: I understand you are in UK
Goods in UK - No extra cost or import implications

**Q: Can I use this product without hair drying my hair afterwards? Can it also be used with the bowl method for my wavy hair?**
A: Hi

The K18 Leave-In Repair Hair Mask is designed to be used as a leave-in treatment, so you don't necessarily need to dry your hair afterwards. It's meant to be applied to damp or towel-dried hair and left in without rinsing. You can simply apply the product and let your hair air dry naturally.

As for using the bowl method with the K18 mask, the bowl method is typically used for deep conditioning treatments, where the hair is saturated with a conditioner or mask and then covered with a shower cap or plastic wrap to enhance absorption. While the K18 mask is not specifically intended for the bowl method, you can certainly try it if you prefer that method. However, keep in mind that the K18 mask is formulated as a leave-in treatment, so it may not have the same effect when used with the bowl method compared to traditional rinse-out masks. It's always a good idea to follow the instructions provided by the manufacturer for the best results.

Have a great weekend!

**Q: Does it weight the hair down? And makes it flat like a keratin treatment does it?**
A: Not at all don’t apply too much, where is your hair damaged the most? Apply it there and brush through! It’s the best thing I’ve ever bought for my extremely damaged coloured fine brittle hair! Buy the small 5ml to try if your not sure. I got 3-4 uses from that tube. Hope this helped x

## Customer Reviews

### ⭐⭐⭐⭐⭐ Game changer
*by S***E on 29 October 2021*

I don't normally write reviews unless I'm absolutely blown away. I saw a couple of negative reviews on here but I purchased anyway after watching some videos on YouTube and I wasn't disappointed. A few days ago I went from brown to blonde at home. As you can see in the picture to the left (and that's before I processed it again with a toner) as you can see there's damage...I knew there would be going back to blonde. The picture to the left is 2 days ago. This morning I shampooed my hair twice with a clarifying shampoo, it's important to really shampoo and to NOT put any conditioner on. Towel dry. .. always gently squeeze the water from the hair with the towel,never rub the hair with a towel when drying. I understand some people will find it hard to not condition but if u stand up in the shower when washing it and dry your hair this way your hair shouldn't be tooo tangly, when you have removed as much excess water as you can apply a SMALL amount... the package has a guideline for the length of hair. I used a pea sized amount and I did think it couldn't possibly be enough but TRUST THE PROCESS! I combed through and left it on probably 10 mins (it says atleast 4 minutes) do not wash it out , after the initial 4 mins you can add styling products, I used a conditioning and heat protecting spray before blow drying. I can't get over how good my hair feels after 1 use, it feels better then pre bleaching, I honestly can't wait to wash my hair again! I will be buying the full size bottle, yes it's expensive but it's insurance for your hair. Its just over 50 pounds on their site for 50mls... that's like a pound per ml and I think i will use 1 ml per use... that's 50 uses for my length hair. I never had results like this with olaplex! I definitely recommend you try the sample size, follow the instructions and you will get a couple of uses...I think I will have 4 uses. This has to be one of the best things I've brought!

### ⭐⭐⭐⭐⭐ Improved hair health and appearance
*by C***Y on 15 January 2025*

I bought the 5ml sample size which was perfect - though it looks tiny it has lasted six applications for my shoulder-blade length, medium thickness, bleach damaged, heat-treated, perimenopausal hair. I had noticed a lot of breakage, especially near my crown. My hair always felt frazzled at the ends and just didn't look shiny or healthy. I used Head and Shoulders clarifying shampoo then K18 for six consecutive washes, followed by Redken Extreme Length leave in conditioner. You have to wait four minutes once you've applied the K18 then style as usual (no need to wash out). It's simple to use in the shower routine and adds no extra time - in fact it saves time as you don't need to use conditioner afterwards. My hair felt softer and healthier after each use and others have complimented my hair. It's not got any particular wow factor after one wash but my hair is now 100% in better condition. Broken ends are smoother and less noticeable, my hair looks so much shinier, fuller and healthier. I'll have a rest from this now but probably do another six washes after my next lightening session to maintain strength and health.

### ⭐⭐⭐ Benefits may depend on hair type
*by O***S on 2 April 2024*

I bought the sample size and the first time I used it got great results. My hair is medium length and very fine. Used to be soft and silky but increasingly prone to dryness and frizz as I get older and greyer. I wash it daily or it looks and feels greasy. K18 says use it every wash for the first 4 or 5 times so I used it again the next day. This time, I didn't like the feel of my hair once dried. It wasn't softer or smoother, and I could feel the product in it. I ended up rewashing it. What I think happens is this. Although K18 is not a protein treatment, it does claim to penetrate the hair. If your hair is thick and porous, it can absorb plenty of product. If it's the opposite, like mine, it can only absorb a little and the excess might build up on the outside of the hair, eventually giving that crunchy feeling. It's what happened when I tried a protein treatment and I think it's what happened here, too. There's still some left in the tiny tube - it's true a little goes a long way - so I might try it again in a couple of months but for me, with my hair type, it would be a very occasional treatment rather than a regular thing and I doubt I'll purchase a larger size.

## Frequently Bought Together

- K18 Biomimetic Hairscience Leave-In Molecular Repair Hair Mask, 5 ml
- Olaplex No. 3 Hair Perfector Repairing Hair Treatment, Concentrated for Dry Damaged Hair, Repairs & Strengthens All Hair Types, 100ml

---

## Why Shop on Desertcart?

- 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016
- 🌍 **Shop Globally** — Access 737+ million products across 21 categories
- 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price
- 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members)
- 🔒 **Secure Payments** — Trusted payment options with buyer protection
- ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews

**Shop now:** [https://www.desertcart.jp/products/365126853-k18-biomimetic-hairscience-leave-in-molecular-repair-hair-mask-5](https://www.desertcart.jp/products/365126853-k18-biomimetic-hairscience-leave-in-molecular-repair-hair-mask-5)

---

*Product available on Desertcart Japan*
*Store origin: JP*
*Last updated: 2026-09-30*