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Longer, thicker, healthier haircheck, check, check.

person showing the before and after effects of using K18 Biomimetic Hairscience Leave-In Molecular Repair Mask on their hair

Byrdie

It would split, break off, and fray at the ends before it got the chance to grow.

Still, I noticed the most drastic change when I started using theK18 Biomimetic Hairscience Leave-In Molecular Repair Mask.

Keep reading for everything there is to know about this magical formula.

K18 Leave-In Molecular Repair Hair Mask

PHOTO: Sephora

How I Use It

This mask’s is, well, different.

And it should only be applied on clean, damp hair.

Then, you better let it sit for four minutes to activate.

Person showing K18 Biomimetic Hairscience Leave-In Molecular Repair Mask cream on their hand and a person showing the before and after effects of using K18 Biomimetic Hairscience Leave-In Molecular Repair Mask on their hair

Byrdie

Once those four minutes are up, you’re able to style your hair as usual.

How Well Did It Work?

But what really took things up a notch was this leave-in mask.

It reversed years of past damage and helped my hair resist future damage.