Schwarzkopf Professional BC Bonacure Color Freeze Silver, 500 ml, Hair Masks for Women, The Schwarzkopf Professional BC Bonacure Color Freeze Silver hair mask is an essential step in your hair care ritual. Give it a moment to regenerate and it will repay you with vitality and beauty. Characteristics: moisturises intensely neutralises yellow undertones in your hair goes deep into the hair fibre How to use: Wash with shampoo, then apply to damp hair. Leave to act as instructed on the packaging, then rinse thoroughly.