Living Proof Perfect hair Day (PhD) Dry Shampoo cleans beyond ordinary dry shampoos. It's powered by Living Proof's patented Healthy Hair Molecule (OFPMA) and Triple-Action Cleaning Technology that absorbs and removes oil, sweat and odor; makes your hair look, feel and smell clean; works on all hair colors because it leaves virtually no visible residue or powdery build-up behind; has a time-released fragrance to deliver a light, clean scent throughout the day.