Clynol Keratin Sleek Silk Sleek Shampoo. This smoothing cleanser is the first step to smoothen your hair for up to 48 hours. It cleans to preserve all the drop dead glamour of the hottest straight look to sweep us into a frenzy. The caring formula coats each hair with a Keratin-Polymer Complex and prepares your hair in the best way for the following steps. You should use the shampoo every time you start your smoothening regime.