The second step of the TRESemm? 7-Day Keratin Smooth System. This Conditioner?s creamy texture helps strengthen the hair, reducing frizz and making the hair softer. For best results, use with the TRESemme 7-Day Smooth Keratin Smooth Conditioner and the TRESemme 7-Day Smooth Keratin Smooth Heat Activated Treatment. Gentle enough for everyday use and for use on colour treated hair.