Rated 4.7 out of 5 stars
8,380 Reviews
leave-in molecular repair hair mask
4-minute leave-in treatment to reverse hair damage
Description
A leave-in treatment mask for all hair types that clinically reverses damage in 4 minutes. The patented peptide technology works to repair damage from bleach, color, chemical services & heat – restoring strength, softness, smoothness, and bounce to hair.
what you can expect
by damage type
backed by science,
loved by stylists
loved by stylists
Our community of stylists and colorists believe K18 is liberating hair—no matter the hair type or generation.
– Christine Thompson, Director of Color at Spoke & Weal
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When hair gets damaged, the polypeptide chains (keratin chains) that make up the inner structure of hair strands become weakened and break. For context, there are billions and billions of polypeptide chains (keratin chains) in a single strand of hair. When these are damaged, hair’s core structure responsible for elasticity and strength becomes compromised and as a result it loses its resiliency and shine—or the look and feel of healthy hair.
After spending a decade in the lab scanning and testing all amino acid sequences across the entire keratin genome that makes up human hair searching for a breakthrough, we discovered one unique sequence (a bioactive peptide) that brings damaged hair back to its original, youthful state. This is our K18Peptide™.
Traveling deeper into the inner layers of hair than traditional repair products, our revolutionary peptide is just the right size and makeup to fit in and reconnect those broken polypeptide chains (keratin chains). And because our peptide is a bit of an overachiever, as a result of this reconnection, any disturbed disulfide bonds are also re-conformed.
Our peptideemploys biomimetics to get the job done. To put it simply: Biomimetics is the practice of learning from and mimicking nature. Mimicking the natural structure of keratin building blocks (amino acid sequences), our K18 bioactive peptide is recognized as natural by the hair. It’s not washed away by water or shampoo like traditional bonding agents either, making K18 a genuine, lasting solution for damaged strands.
After spending a decade in the lab scanning and testing all amino acid sequences across the entire keratin genome that makes up human hair searching for a breakthrough, we discovered one unique sequence (a bioactive peptide) that brings damaged hair back to its original, youthful state. This is our K18Peptide™.
Traveling deeper into the inner layers of hair than traditional repair products, our revolutionary peptide is just the right size and makeup to fit in and reconnect those broken polypeptide chains (keratin chains). And because our peptide is a bit of an overachiever, as a result of this reconnection, any disturbed disulfide bonds are also re-conformed.
Our peptideemploys biomimetics to get the job done. To put it simply: Biomimetics is the practice of learning from and mimicking nature. Mimicking the natural structure of keratin building blocks (amino acid sequences), our K18 bioactive peptide is recognized as natural by the hair. It’s not washed away by water or shampoo like traditional bonding agents either, making K18 a genuine, lasting solution for damaged strands.
Our patented peptide is a unique sequence of amino acids that travels deep into hair’s core structure to fit in and reconnect broken polypeptide chains (keratin chains) responsible for hair strength and elasticity.
An Analogy: When building proteins, the order of the amino acids determines the kind of protein and its properties, much like the way letters are arranged to make meaningful words and sentences. In the same way the order and where each word sits in a sentence leads to its overall meaning, K18 is the magic word that fits right in, integrating itself with the keratin chains as the hair recognizes it as a natural building block.
An Analogy: When building proteins, the order of the amino acids determines the kind of protein and its properties, much like the way letters are arranged to make meaningful words and sentences. In the same way the order and where each word sits in a sentence leads to its overall meaning, K18 is the magic word that fits right in, integrating itself with the keratin chains as the hair recognizes it as a natural building block.
K18 is most effective on clean, towel-dried hair. Conditioners use silicones and conditioning agents that form heavy coatings on hair , preventing our peptide from reaching the broken polypeptide chains deep inside hair’s inner layer.
We like to keep our formulas minimal, only using the exact amount of ingredients needed to get the peptide where it needs to go. Our unique blend of 3 alcohols function to open up the hair cuticle so the K18Peptide ™ can penetrate the inner most layer of hair, reaching the broken polypeptide chains (keratinchains). Here the alcohol serves as an agent to optimize the hair environment for K18 to work on a deeper level.
You will start to see stronger, softer, healthier hair after just one use.
Renews strength, softness, smoothness, and bounce
Reviews Summary
Generated by AI from 100 most recent customer reviews
Last updated 5 months ago
Customers say this leave-in hair mask transforms their hair texture and manageability after just one use. Many reviews mention noticeable improvements in softness and reduced frizz. Users with curly, fine, and color-treated hair report positive results. The mask works well for various hair types, with many noting improved texture and easier styling. While some mention the product's high price point, most find a little goes a long way. A few users recommend using conditioner alongside the mask for best results. Reviews consistently highlight the mask's effectiveness for addressing dry, brittle hair concerns.
8,380 reviews
- Theresa M. M.Verified BuyerReviewingMini Leave-In Molecular Repair Hair Mask 15 mLI recommend this productAge 65+Hair Concern Chemical damage, Heat damage, Color-care, Frizz, DrynessHair Type Fine/Thin, Grey HairMy Results Less Frizz, Visible Difference, Less Breakage, Shinier Hair, Smoother HairRated 5 out of 5 stars4 days agoLeave in Hair Mask
Amazing product!! I have many fine hair most products weigh it down or matter it fuzzy! This product dues neither best thing I have found!!!
KK18Hair2 days agoWe love hearing this! We’re so glad you finally found something that keeps your fine hair soft, light, and frizz-free. Thanks for sharing your K18 results, Theresa!
- Emily S.Verified BuyerReviewingFull-Size Leave-In Molecular Repair Hair Mask 50mLI recommend this productAge 25 - 34Hair Concern Chemical damage, FrizzHair Type Medium DensityMy Results Less Frizz, Visible Difference, Less Breakage, Stronger Hair, Smoother HairRated 5 out of 5 stars1 week agoThis worked after just two uses!
I took a before photo to ask Chat GBT what product to use and it recommended K18. I have used it twice on damp hair per the instructions and already my hair looks much better! The second photo is my after picture.
KK18Hair6 days agoWow, we love to hear it! So happy K18 is already making such a visible difference. Thanks for sharing your before and after journey with us, Emily!
- Ginny B.Verified BuyerReviewingLeave-In Molecular Repair Hair Mask SampleI recommend this productRated 5 out of 5 stars2 weeks agoWow curls
Just one use and my wavy/curly yet frizzy hair became those silky gorgeous curls again with very little frizz. WOW! I thought age had taken them away. Nope just damage.
KK18Hair2 weeks agoWe're so thrilled to hear about your gorgeous curls coming back to life, Ginny! Thank you for sharing your wonderful experience! 🙌
- Ann M. R.Verified BuyerReviewingMini Leave-In Molecular Repair Hair Mask 15 mLI recommend this productAge 25 - 34Hair Concern Extending time between washesHair Type Straight/WavyMy Results Less Frizz, Visible Difference, Smoother Hair, Cleaner, fresher hair, Oil absorbedRated 5 out of 5 stars3 weeks agoLoving my Hair with Molecular Repair
Love it makes my hair shine and it behaves wonderfully
KK18Hair2 weeks agoThanks for the amazing 5-star review!
- Esther Y.Verified BuyerReviewingFull-Size Leave-In Molecular Repair Hair Mask 50mLI recommend this productAge 35 - 44Hair Concern Chemical damage, Fragile/brittle hair, Color-care, DrynessRated 5 out of 5 stars3 weeks agoHair repair
My bleached hair was so brittle and dry. K18 hair mask saved it after 2-3 uses
KK18Hair2 weeks agoIt's amazing how quickly it can work its magic on damaged hair. Thanks for the amazing 5-star review!
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