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White half-ounce bottle of K18 Biomimetic Hairscience Leave-in Molecular Repair Hair Mask on a bright lime green background
White 1.7 ounce bottle of K18 Biomimetic Hairscience Leave-in Molecular Repair Hair Mask on a bright lime green background
Bottle of K18 Leave-In Molecular Repair Hair Mask on pink-orange background is labeled with its key benefits in white lettering
Bottles of K18 Leave-In Molecular Repair Hair Mask rest on swaths of white creamy product and next to droplets representing recommended application sizes
Bottle of K18 Molecular Repair Mask in front of a molecule chain structure on a rainbow ombre background is captioned, "Clinically proven to reverse damage from bleach + color, chemical services, and heat"
Side-by-side comparison of hair after bleach with and without K18 mask is captioned, "Biotech-powered K18PEPTIDE™ reverses hair damage in 4 minutes"
Side-by-side comparison of curly hair before and after K18 mask as posted by @rocolbeautystudio on a rainbow ombre background
Flow chart in white on pink-purple ombre background is labeled, "Where does K18 fit into your routine?"
White 5 ounce bottle of K18 Biomimetic Hairscience Leave-in Molecular Repair Hair Mask on a bright lime green background
White half-ounce bottle of K18 Biomimetic Hairscience Leave-in Molecular Repair Hair Mask on a bright lime green background
White 1.7 ounce bottle of K18 Biomimetic Hairscience Leave-in Molecular Repair Hair Mask on a bright lime green background
Bottle of K18 Leave-In Molecular Repair Hair Mask on pink-orange background is labeled with its key benefits in white lettering
Bottles of K18 Leave-In Molecular Repair Hair Mask rest on swaths of white creamy product and next to droplets representing recommended application sizes
Bottle of K18 Molecular Repair Mask in front of a molecule chain structure on a rainbow ombre background is captioned, "Clinically proven to reverse damage from bleach + color, chemical services, and heat"
Side-by-side comparison of hair after bleach with and without K18 mask is captioned, "Biotech-powered K18PEPTIDE™ reverses hair damage in 4 minutes"
Side-by-side comparison of curly hair before and after K18 mask as posted by @rocolbeautystudio on a rainbow ombre background
Flow chart in white on pink-purple ombre background is labeled, "Where does K18 fit into your routine?"
White 5 ounce bottle of K18 Biomimetic Hairscience Leave-in Molecular Repair Hair Mask on a bright lime green background
White 1.7 ounce bottle of K18 Biomimetic Hairscience Leave-in Molecular Repair Hair Mask on a bright lime green background
Bottle of K18 Leave-In Molecular Repair Hair Mask on pink-orange background is labeled with its key benefits in white lettering
Bottles of K18 Leave-In Molecular Repair Hair Mask rest on swaths of white creamy product and next to droplets representing recommended application sizes
Bottle of K18 Molecular Repair Mask in front of a molecule chain structure on a rainbow ombre background is captioned, "Clinically proven to reverse damage from bleach + color, chemical services, and heat"
Side-by-side comparison of hair after bleach with and without K18 mask is captioned, "Biotech-powered K18PEPTIDE™ reverses hair damage in 4 minutes"
Side-by-side comparison of curly hair before and after K18 mask as posted by @rocolbeautystudio on a rainbow ombre background
Flow chart in white on pink-purple ombre background is labeled, "Where does K18 fit into your routine?"
White half-ounce bottle of K18 Biomimetic Hairscience Leave-in Molecular Repair Hair Mask on a bright lime green background
White 5 ounce bottle of K18 Biomimetic Hairscience Leave-in Molecular Repair Hair Mask on a bright lime green background
White 1.7 ounce bottle of K18 Biomimetic Hairscience Leave-in Molecular Repair Hair Mask on a bright lime green background
Bottle of K18 Leave-In Molecular Repair Hair Mask on pink-orange background is labeled with its key benefits in white lettering
Bottles of K18 Leave-In Molecular Repair Hair Mask rest on swaths of white creamy product and next to droplets representing recommended application sizes
Bottle of K18 Molecular Repair Mask in front of a molecule chain structure on a rainbow ombre background is captioned, "Clinically proven to reverse damage from bleach + color, chemical services, and heat"
Side-by-side comparison of hair after bleach with and without K18 mask is captioned, "Biotech-powered K18PEPTIDE™ reverses hair damage in 4 minutes"
Side-by-side comparison of curly hair before and after K18 mask as posted by @rocolbeautystudio on a rainbow ombre background
Flow chart in white on pink-purple ombre background is labeled, "Where does K18 fit into your routine?"
White half-ounce bottle of K18 Biomimetic Hairscience Leave-in Molecular Repair Hair Mask on a bright lime green background
White 5 ounce bottle of K18 Biomimetic Hairscience Leave-in Molecular Repair Hair Mask on a bright lime green background

K18 - Leave-In Molecular Repair Hair Mask

K18
$29.00
  • Mini
  • 1.7 oz
  • Professional Size: 5 oz

Leave-in treatment that works on the molecular level to reverse hair damage in just four minutes. Patented K18PEPTIDE™ is clinically proven to repair damage from bleach and color, chemical services, and heat, with immediate and lasting results to restore strength, softness, smoothness, and bounce. (Immediate and progressive results observed in scientific-technical testing on hair tresses damaged by 450°F heat after one 4-minute application of mask.)

Key Benefits:
• Reconnects both polypeptide chains and disulfide bonds for strength along the length and width of the hair, offering comprehensive, lasting damage repair.
• Restores hair from even extreme damage by working at the innermost layer, restoring core strength and elasticity for strong, smooth, bouncy hair.
• Hair is repaired from the first use and lasts past your next wash for ongoing reparative benefits.
• Convenient leave-in formula works in just 4 minutes with no extra rinse required.
• Because K18PEPTIDE™ works on a molecular level (where all hair is the same), it is effective on all hair types.
• Cream format enables easy, lightweight application across all hair types with detangling and softening benefits.
• pH-optimized (5.0-6.0) to help minimize cuticle swelling and put hair proteins in their most resilient state.
• K18PEPTIDE™ mimics hair’s structure to reverse damage by reconnecting polypeptide chains and disulfide bonds broken during bleaching, coloring, chemical services, and heat.
• Vegan, color-safe, and cruelty-free

How to Use:
After shampooing, towel-dry hair thoroughly. Do not condition. Apply 1-3 pumps of mask (based on your hair length and density) starting at the ends and working your way up toward the roots. Let sit 4 minutes. Do not rinse. Comb, add product, and style as usual. Use for 4-6 washes post-salon service, then as needed.

Dos and Don’ts:
✔︎ DO clarify/demineralize before K18 if you’re a heavy product user
✔︎ DO apply to 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 consecutive shampoos for progressive results
✘ DON’T use conditioner before applying K18 ask (you may apply after 4 minutes of mask treatment but most find they don’t need it)
✘ DON’T overdo it—less is more
✘ DON’T rinse it out