•  

    soft, strong, bouncy hair for everyone

    Biology-first routines deliver lasting results for every hair type, color, texture, and style.

    SHOP NOW
  •  

soft, strong, bouncy hair for everyone

Biology-first routines deliver lasting results for every hair type, color, texture, and style.

SHOP NOW

your healthiest hair starts here

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full-size leave-in molecular repair hair mask

Description

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.

20+ billion TikTok views 🔥 

Repairs Damage Caused By

Bleach + Color

Heat

Chemical Services

how to use

  1. Shampoo, do not condition. Towel-dry thoroughly.
  2. 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.
  3. Let sit for 4 minutes. Do not rinse out.
  4. Comb, add product + style as usual. Use for 4-6 washes post-salon service, then as needed.

more to know

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.

key benefits

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.

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.

Try it now

jumbo leave-in molecular repair hair mask

Description

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.

20+ billion TikTok views 🔥 

Repairs Damage Caused By

Bleach + Color

Heat

Chemical Services

more to know

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.

key benefits

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.

how to use

  1. Shampoo, do not condition. Towel-dry thoroughly.
  2. 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.
  3. Let sit for 4 minutes. Do not rinse out.
  4. Comb, add product + style as usual. Use for 4-6 washes post-salon service, then as needed.

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.

Try it now

    DAMAGE SHIELD Protective Conditioner

    Description

    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.

    20+ billion TikTok views 🔥 

    protects from damage for up to 3 days from:

    UV rays

    mechanical styling

    environmental aggressors

    how to use

    1. Apply a small amount of DAMAGE SHIELD protective conditioner from mid-lengths to ends and build as needed.
    2. Rinse thoroughly.
    3. For best results, use after shampooing with DAMAGE SHIELD shampoo.

    more to know

    Clinically proven to provide conditioning protection against damage from UV rays, mechanical styling, and environmental aggressors for up to 3 days*. Fortifies, softens, and detangles hair.

    Defends against damage: Conditioning protection against damage from UV rays, environmental aggressors, and daily mechanical styling for up to 3 days.

    Maintains hair health: Fortifies hair’s exterior lipid barriers to make hair more resilient and resistant to damage. K18PEPTIDE™ replenishes protein lost during washing.

    Enhances hair’s natural shine: pH-optimized formula minimizes excess cuticle swelling during washing to help keep hair smooth and maximize shine.

    Softens, smooths, and detangles: Without film-forming silicones or waxes that can build up over time and weigh hair down.

    *Disclaimers

    key benefits

    Biotech-Produced Polysaccharide acts as a biomimetic shield to protect hair against pollution and environmental aggressors.

    Fortifying Ceramide Blend seals damage sites in the hair cuticle—smoothing and protecting hair from further damage.

    K18PEPTIDE™ replenishes protein lost during washing.

    ingredients

    Water (Aqua) (Eau), Isopropyl Palmitate, Stearyl Alcohol, Propanediol, Isopentyldiol, Behentrimonium Chloride, Tocopherol, Tocopheryl Acetate, sh-Oligopeptide-78, Alteromonas Ferment Extract, Prunus Amygdalus Dulcis (Sweet Almond) Oil, Simmondsia Chinensis (Jojoba) Seed Oil, Phospholipids, Jojoba Esters, Calcium Gluconate, Hydroxypropyl Guar Hydroxypropyltrimonium Chloride, Ceramide NP, Phytosteryl/Isostearyl/Cetyl/Stearyl/Behenyl Dimer Dilinoleate, Polyquaternium-16, Stearalkonium Chloride, Isopropyl Alcohol, Butylene Glycol, Gluconolactone, Phenoxyethanol, Sodium Benzoate, Citric Acid, Sodium Hydroxide, Fragrance (Parfum), Hydroxycitronellal.

    clinically proven protection

    3%

    Days of conditioning protection against damage from UV rays, mechanical styling, and environmental aggressors*

    94%

    agreed hair didn't feel weighed down*

    91%

    agreed hair felt softer*

    Try it now

    Real people, real results

    "I absolutely love this product!! You have to see it to believe it!"- Christina Marie P.

    Before

    After

     
     

    Amazing the way it feels and the shine provides to the hair instantly" -Sandra M.

    Before

    After

     
     
     
    •  

      Powered by K18PEPTIDE

      Biomimetic peptide bonds with hair’s keratin structure—the source of its core strength—for soft, shiny, and bouncy results that won’t wash away.

    How to use molecular repair mask

    1. Shampoo, do not condition. Towel-dry thoroughly.

    2. Apply 1-3 pumps based on your length and density, starting at the ends and working up towards the roots.

    3. Let sit for 4 minutes. Do not rinse out.

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

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    Reviews from repeat customers

    FAQS

    What’s the difference between these three products?

    The two Leave-In Molecular Repair Hair Masks (50 mL and 100 mL) are the same formula — only the size is different. This leave-in treatment works on a molecular level to repair damage from bleach, color, heat, and chemical services.

    The Damage Shield Protective Conditioner is a rinse-out conditioner designed to protect hair from daily stress like UV rays, mechanical styling, and environmental aggressors.

    In short:

    • The mask repairs internal hair damage (leave-in).
    • The conditioner protects the hair’s surface (rinse-out).

      Use the mask if your hair is damaged, and the conditioner for ongoing protection.

    How do I use the Leave-In Hair Mask? Do I rinse it out?

    Nope — it’s a leave-in formula.

    1️⃣ Shampoo your hair (don’t use conditioner).

    2️⃣ Towel-dry until hair is damp, not dripping.

    3️⃣ Apply 1–3 pumps from ends to roots, depending on hair length and thickness.

    4️⃣ Wait 4 minutes for the peptide to activate.

    5️⃣ Do not rinse out — style as usual.

    💡Use it for the first 4–6 washes after chemical services, then as needed for maintenance.

    Can I use the conditioner with the mask?

    Yes, but not at the same time.

    • Use the Damage Shield Protective Conditioner after shampooing and rinse it out — it’s meant for daily or regular protection.
    • The Leave-In Mask should be used on clean, towel-dried hair without conditioner beforehand so the peptide can fully absorb.

      Think of it this way:

      🧪 Mask = Repair

      🛡️ Conditioner = Protection

    Is it suitable for fine or oily hair?

    Absolutely. K18’s patented K18PEPTIDE™ works for all hair types.

    For fine or oily hair, just start with less — a little goes a long way! The mask is highly concentrated, so use only 1–2 pumps and focus on the ends.

    The Damage Shield Conditioner also has a lightweight, silicone-free formula, so it won’t weigh down fine strands.

    I see alcohol in the ingredients — will it dry out my hair?

    Good question! Yes, the formula includes alcohol denat., but it’s there for a reason.

    It helps open the hair cuticle so the K18PEPTIDE™ can penetrate deeply and repair the inner structure. The formula is pH-balanced (around 5.0–6.0) to stay gentle and minimize dryness.

    Unless your scalp is very sensitive, it shouldn’t cause irritation. Always start with a small amount and see how your hair responds.

    How long until I see results, and how long do they last?

    Most people notice stronger, smoother hair after just 2–3 uses, and results last beyond your next wash.

    For the Damage Shield Conditioner, the protective effect lasts up to 3 days, shielding your hair from UV rays, heat, and mechanical stress.

    For damaged or chemically treated hair, use the mask for 4–6 consecutive washes to rebuild the hair’s structure and then switch to regular maintenance.