This four piece set includes all three steps of the Density Hair Care System, giving you the foundation for thicker, healthier more voluminous looking hair. STIMUL8 SHAMPOO: 10 fl oz /300 ml bottle Supports hair strength and defends against breakage Reduces build-up and promotes scalp microcirculation Leaves hair ultra-clean, as it helps clear away impurities at the follicle to improve the effectiveness of ACCELER8 Hair Booster + Nutrients EXHILAR8 CONDITIONER: 10 fl oz /300 ml bottle Improves manageability, combability and detangling Adds visible body and volume to the hair Naturally derived amino acids which are the building blocks to help strengthen hair ACCELER8 HAIR BOOSTER + NUTRIENTS: 4 fl oz/125 ml bottle Light activated ingredient Instantly thickens to provide lift to the hair at the root Four sources of ENERGY RSN8 PRO SCALP TREATMENT: 2 fl oz /60 ml bottle Helps fight the signs of biological aging Nourishes and moisturizes hair and scalp Provides peptides, anti-oxidants, amino acids and extracts crucial for a youthful scalp