Works inside and out to repair texture and to add epic shine with the Color Wow Pop & Lock Crystallite Shellac. Loaded with re-lubricating humectants, 75% of the formula works inside the hair to help restore elasticity and suppleness. Then, the serum portion of the formula wraps around the outside of the hair, forming a crystal clear, high-gloss sheath to lockdown the cuticle and lock in the lubricants. Hair color pops, texture is transformed. Color Wow is a cruelty-free brand; they do not test any of their products on animals.