For Professional Use Only: Clairol Pure White 20 Volume Creme Developer mixes easily with any Clairol Professional hair color or lightener into a creamy consistency. Ideal for bowl-and-brush application. Provides a slightly thicker, more opaque mixture. Laboratory stabilized to guarantee consistent, predictable results. Designed for standard lightning action, superior gray coverage. For use with all Clairol Professional lighteners. Guaranteed fresh for three years.