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K18 Leave-In Molecular Repair Hair Mask

$43.50$75.00

K18 leave-in repair mask 50 ml white pump bottle, front view

K18 Leave-In Molecular Repair Hair Mask

$43.50$75.0042% off
  • Works in 4 minutes, no rinse needed
  • Targets bleach, color and heat damage
  • 1 to 3 pumps, based on hair length
  • Made for all hair types
  • Vegan, color-safe, cruelty-free

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Leave-in molecular repair mask

The repair mask you leave in

K18 built this mask around the K18PEPTIDE, a biotech-developed peptide that mimics hair's structure and reconnects the polypeptide chains and disulfide bonds broken by bleach, color, chemical services and heat. Apply it to clean, towel-dried hair, wait 4 minutes and style as usual.

Repair at the molecular level

The peptide reaches the innermost layer of the hair to reconnect broken polypeptide chains, and with them disulfide bonds, renewing strength along the length and width of each strand, according to K18.

Four minutes, no rinse

There is no processing time to plan around. Shampoo, skip conditioner, apply one to three pumps and wait four minutes before combing or adding your usual styling products.

Made for every hair type

Because the peptide works at the molecular level, where all hair is the same, K18 says the mask suits all hair types. The pH-optimized cream, 5.0 to 6.0, also detangles and softens.

K18 Leave-In Molecular Repair Hair Mask, closer in

How to use

Shampoo, skip conditioner, wait four minutes

Shampoo without conditioner and towel-dry thoroughly. Apply 1 to 3 pumps based on length and density, starting at the ends and working up toward the roots. Let it sit for 4 minutes, then comb, add product and style. Do not rinse.

  • Start with 1 pump and add more as needed.
  • Use for 4 to 6 washes after a salon service.
  • Clarify first if you use a lot of product.
Why do I skip conditioner before it?

K18 explains that conditioner leaves a film that blocks the peptide from penetrating. Once the 4 minutes are up, you can use a conditioner, a leave-in or any other product you like.

Do I rinse it out?

No. It is a leave-in treatment: apply it to clean, towel-dried hair, wait 4 minutes and style as usual, without rinsing.

How much should I use?

Start with 1 pump and add more as needed. K18 recommends 1 to 3 pumps depending on your hair's length and density, with an average of 2 pumps. The formula is concentrated, so less is more.

How often should I use it?

K18 recommends 4 to 6 consecutive washes after a salon service, then every other wash or as needed.

Will it work on my hair type?

Yes. K18 says it is effective on all hair types, because the peptide works at the molecular level, where all hair is the same. It is vegan, color-safe and cruelty-free.

When will I notice a difference?

K18 says results usually show after 2 to 3 uses, and that the more damaged the hair, the more visible the change. Results vary with hair type and level of damage.

Why is there alcohol in the formula?

K18 uses a blend of three alcohols to open the hair cuticle so the peptide can reach the innermost layer of the hair, where the broken keratin chains are.

Can I return it once opened?

Opened hair care can't be resold, so it is returnable only if it arrived damaged or was the wrong item. Sealed and unopened, you have 30 days from delivery to start a return.

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The whole sheet

  • TechnologyBond building
  • Volume50 ml
  • Key ingredientssh-Oligopeptide-78 (biomimetic peptide)
  • Hair typeAll hair types, Damaged, Color-treated
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