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K18 K18 - Leave-in Molecular Repair Hair Mask (50ml)

K18 - Leave-in Molecular Repair Hair Mask (50ml)

Brand K18
New

In stock

Product overview:

  • Takes damage repair further – reconnects both polypeptide chains (and as a result, also reconnects disulfide bonds) for strength along the length + width of the hair - offering comprehensive, lasting damage 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.

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£40.00
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Delivery: Standard (Free) | Mon 16th - Fri 20th Nov

Sold by: Zalviro, there are 7 other sellers

Returns: 30 days

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Description & Details

Summary

  • Takes damage repair further – reconnects both polypeptide chains (and as a result, also reconnects disulfide bonds) for strength along the length + width of the hair - offering comprehensive, lasting damage 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.

K18 - Leave-in Molecular Repair Hair Mask (50ml) Description

K18 - Leave-in Molecular Repair Hair Mask (50ml) This patented bioactive peptide treatment strengthens and improves elasticity while reversing damage from chemical services, thermal styling, and mechanical styling. For all hair types. Hair like new. This leave-in mask heals and strengthens hair with lightweight moisturizing benefits to detangle and keep hair smooth and soft, without weighing it down. Please see dosage chart for exact usage. For best results, use for the first 4-6 consecutive washes following a service, and then every 3-4 washes as needed to maintain hair strength.

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.

how to use:

Shampoo, do not condition. Towel-dry thoroughly.

Apply 1-3 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.

Let sit for 4 minutes. Do not rinse out.

Comb, add product + style as usual. Use for 4-6 washes post-salon service, then as needed.

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 + heat*.

pH-optimized (5.0-6.0) to help minimize cuticle swelling + put hair proteins in their most resilient state.

Cream format enables easy, lightweight application across all hair types, with detangling and softening benefits.

Vegan, color-safe, cruelty-free.

Dos and don'ts:

DO clarify before K18 if you're 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.

DO use for 4-6 shampoos consecutively for progressive results.

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.

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.

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.

Details

OPC P9GPSC7
Brand
Codes 0858511001128 (EAN)
Rank Hot
Links K18 Hair Masks

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Reviews of K18 - Leave-in Molecular Repair Hair Mask (50ml)

All OnBuy Reviews are Verified Reviews

Overall Rating:
5
50 Reviews
4
2 Reviews
3
0 Reviews
2
0 Reviews
1
0 Reviews
Highest Rated Review
5/5
m. rogers
Posted 27/10/2026
happy with the product just not the delivery or timeframe waited far too long
Filter Reviews
5/5
m. rogers
Reviewed from GB
Posted 27/10/2026
happy with the product just not the delivery or timeframe waited far too long
5/5
L. Monkman
Reviewed from GB
Posted 24/10/2026
I love this product I’ve used it before but the price puts me off but on buy is so competitive and I got it at a fantastic price , so I will continue using this product and have fantastic hair
5/5
N. Oğuz
Reviewed from GB
Posted 13/08/2026
Sold By AREASYBUYLTD
Im very happy with K18 and seller very good they sent me quickly will keep buy from this seller
5/5
Z. stockton
Reviewed from GB
Posted 18/04/2026
Quick delivery and products as expected
5/5
D. Dobre
Reviewed from GB
Posted 17/03/2026
Sold By kms printers
Good product.Leaves the hair soft and healty.
5/5
J. Davey
Reviewed from GB
Posted 14/03/2026
Sold By Vilus Beauty
Great purchase have only used it once with great results exactly as product description and easily applied.
5/5
M. Mcmanus
Reviewed from GB
Posted 28/01/2026
Sold By ZORVATH LTD
Very happy with tgd product
5/5
N. Sutherland
Reviewed from GB
Posted 19/01/2026
Love this product, great price and makes my bleached hair feel as good as new!
5/5
L. Miller
Reviewed from GB
Posted 08/01/2026
Really happy with this product, best i have ever used, can see results after one use!
5/5
S. Parkyn
Reviewed from GB
Posted 08/12/2025
Seems ok, not used yet. I was worried it might be a fake but packaging same as previous full price purchase
5/5
J. Anderson
Reviewed from GB
Posted 29/11/2025
Just received my product . Happy with it so far.
5/5
A. McNeill
Reviewed from GB
Posted 13/11/2025
Very pleased with my purchase. Hairdresser commented that my hair was in good condition. I will only use the product a couple of times a month - that’s plenty.
5/5
C. Burrow
Reviewed from GB
Posted 13/11/2025
Sold By NORIOX LTD
I'm very happy with for product and really helped my hair.
5/5
Z. Bull
Reviewed from GB
Posted 02/11/2025
Happy with the product, little cheaper than other site's, so very happy and a quick delivery.
5/5
H. Clarke
Reviewed from GB
Posted 28/10/2025
LOVE this price of this amazing product. One use and I can notice a difference. I only wash my hair one a week, but already can’t wait to wash it again! Highly recommend!
5/5
T. Ireland
Reviewed from GB
Posted 21/10/2025
Sold By J&L Hub
Only used this twice now, but it seems like the real deal. I was apprehensive about not using conditioner but it's not needed at all, my hair feels soft and I love that I don't need to rinse it out. I'll continue to use this after shampooing and see what magic it can work. At this price I'm happy to give it a try.
5/5
C. Stone
Reviewed from GB
Posted 28/09/2025
Great product at a great price. It was a bit flow to arrive but the vendor responded promptly and it arrived safely . Thank you
5/5
C. Briggs
Reviewed from GB
Posted 02/09/2025
Happy with product as described. Prompt delivery
5/5
D. Mason
Reviewed from GB
Posted 02/09/2025
The best keave-in conditioner I've ever purchased - the best price on this website (Onbuy)- I will be purchasing again and again! Thank you for quick delivery and great prices!
5/5
T. Fuller
Reviewed from GB
Posted 01/09/2025
Love this product
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