THIS IS A PROFESSIONAL USE PRODUCTRusk's shine-enhancing cream developers have a whole new look Universal, for use with every Rusk colour line (excluding RUSKin10) For optimal and predictable colour results and superior gray coverage Produces the proper pH to ensure maximum tone, depth and color durability without compromising the integrity of the hair fiber Active conditioning agents ensure that the hair looks and feels healthy, soft and shiny Tighter portfolio = space saver, less inventory Use RUSK Zero Lift Developer with: Deepshine Gloss & Deepshine Xpress Gloss Deepshine Permanent Colour RUSK Lighteners USAGE TIPS: Refer to colour & lightener mixing guidelines on wall charts and swatch book to ensure superior gray coverage or proper usage with lightener.