K18 · Leave-in molecular repair · K18PEPTIDE™
K18 Leave-In Molecular Repair Hair Mask
4 minutes, no rinse · After shampoo, no conditioner first · 50 ml or 150 ml
A leave-in treatment, not a conditioner: after shampooing, towel-dry, work in one to three pumps, wait four minutes and style. The K18PEPTIDE™ (sh-Oligopeptide-78) was developed from keratin-peptide research at the University of Minho in Portugal and is built to get past the cuticle into the keratin structure of hair damaged by bleach, colour, heat and chemical services. Most people notice the difference within two to three uses.
- 4 minutes, no rinse
- 1–3 pumps, from the ends up
- Results within 2–3 uses
BUY MORE, SAVE MORE
Notify me when it's back
Leave your email and we'll be in touch the moment this is back in stock.
One email about this product only. No newsletter, no spam.
Couldn't load pickup availability
What it does well
- K18PEPTIDE™ (sh-Oligopeptide-78): a biomimetic peptide that mimics keratin and works inside the hair, not on the surface
- Four minutes, then style. Nothing to rinse, nothing to leave in overnight
- For damage from bleach, colour, heat and chemical services, on every hair type
- Lab-tested on bleached hair fibres: stronger, more elastic and twice as resistant to breakage after one 4-minute application (K18 testing)
- pH-optimised at 5.0–6.0; vegan, colour-safe and cruelty-free according to K18
What it is not
- Not a conditioner: conditioner before K18 blocks the peptide, and most hair does not need one after
- Not gluten-free: it contains hydrolysed wheat protein, so ask your doctor first if you have a wheat allergy
How to use it
Shampoo, skip conditioner, towel-dry thoroughly. Apply 1–3 pumps depending on length and thickness, from the ends up towards the roots. Wait 4 minutes. Do not rinse. Then style as usual; if the hair still needs it, a conditioner or leave-in may go on after the four minutes. Use for 4–6 washes in a row after a salon service, then once or twice a week as needed. Heavy product user? Clarify first.
- sh-Oligopeptide-78
- Leave-in
- Vegan
- Colour-safe
- pH 5.0–6.0
- Contains wheat protein
Real people, real routines
Unfiltered videos from people using K18. Tap a video for sound.
-
K18 mask · first try, 4 minutes
-
K18 mask · hair strength test
-
K18 AirWash · day-3 hair
-
K18 AirWash · after a workout
-
K18 AirWash · oily-hair test
For faster & better results
K18 Leave-In Molecular Repair Hair Mask
A leave-in treatment, not a conditioner: after shampooing, towel-dry, work in one to three pumps, wait four minutes and style. The K18PEPTIDE™ (sh-Oligopeptide-78) was developed from keratin-peptide research at the University of Minho in Portugal and is built to get past the cuticle into the keratin structure of hair damaged by bleach, colour, heat and chemical services. Most people notice the difference within two to three uses.
What it does well
- K18PEPTIDE™ (sh-Oligopeptide-78): a biomimetic peptide that mimics keratin and works inside the hair, not on the surface
- Four minutes, then style. Nothing to rinse, nothing to leave in overnight
- For damage from bleach, colour, heat and chemical services, on every hair type
- Lab-tested on bleached hair fibres: stronger, more elastic and twice as resistant to breakage after one 4-minute application (K18 testing)
- pH-optimised at 5.0–6.0; vegan, colour-safe and cruelty-free according to K18
What to expect
- Wash 1: Shampoo, no conditioner, towel-dry. 1–3 pumps, 4 minutes, style. Hair should already feel softer.
- Washes 2–6: Use it every wash for 4–6 washes after a bleach, colour or chemical service. Most people see the difference by use 2–3.
- After that: Once or twice a week, or as needed. The more damaged the hair, the bigger the difference tends to be.
The honest part
- Repair, as K18 defines it: K18 says it reverses damage and restores strength and elasticity. Its evidence is lab testing on bleached hair fibres, not a published clinical trial on people, so we describe it as repairing the look, feel and strength of damaged hair.
- Wheat, so not gluten-free: The formula contains hydrolysed wheat protein and wheat starch. K18 advises anyone with a wheat allergy to check with a doctor first. We do not claim gluten-free.
- 150 ml is the salon size: K18's consumer sizes are 15, 50 and 100 ml. The 150 ml is the K18 Professional size made for salons: same formula, more of it.
Shipping:
Orders placed before 23:00 (UK time) on a business day are usually dispatched the same day. Standard delivery takes 5–8 business days, depending on the country. Shipping costs €5.99 and is free on orders from €80 (or the equivalent in your currency). As soon as your order ships, you receive a confirmation e-mail with a tracking link.
Returns:
We want you to be completely satisfied with your purchase. If, for any reason, you are not satisfied with a product purchased from us, you have the right to return it within 30 days of receipt for a refund or exchange. Please keep the following points in mind:
- The returned product must be in the same condition as when you received it, including all original packaging and labels.
- Returns must be approved in advance. Please contact us to arrange a return and receive the necessary instructions.
- Return shipping costs are your responsibility, unless the product is defective or does not match the description.
- Once we have received and inspected the returned product, we will process the refund or ship a replacement product, depending on your preference.
Contact us:
If you have any questions about shipping, returns, or a specific product, please don’t hesitate to contact us. Our customer service team is ready to assist you and answer all your questions.
We appreciate your trust in us and are committed to providing you with the best possible shopping experience.
120-day satisfaction guarantee:
Separately from the 30-day right of return above, every order is covered by our 120-day satisfaction guarantee. Hair regrowth takes 3 to 6 months, so you get time to judge the results properly.
What it is not
- Not a conditioner: conditioner before K18 blocks the peptide, and most hair does not need one after
- Not gluten-free: it contains hydrolysed wheat protein, so ask your doctor first if you have a wheat allergy
Sources and warnings
Cosmetic product. Avoid contact with eyes; stop if irritation occurs; contains fragrance allergens and wheat protein. Not a hair loss treatment. ¹ K18 testing on bleached hair fibres after one 4-minute application, as published in K18's disclaimers; not a clinical study on people.