Used twice Meet the leave-in treatment that instantly repairs and forever protects. Named as one of TIME’s Best Inventions of 2024, this new product revolutionizes hair repair by not only instantly repairing existing damage, but fighting future damage. Packed with the highest percentage of our hair-identical protein, Alpha Keratin 60ku®, this wonder-working miracle serum instantly repairs the severed bonds that give hair its strength, naturally restores damaged peptides to give hair elasticity, and refills each strand with keratin to smooth, soften, and protect from future harm.