Bauman Collective Silk Sleep Cap Made of 100% Pure Mulberry Silk 22 Momme Silk Sleep Caps are fantastic for eliminating bed head, preventing breakage and keeping hair hydrated while you sleep. Wake up with shiny, hydrated hair. Sleep Caps are a chic turban style, with a knot in the front and an elastic band in the back so it stretches and forms to all head shapes and sizes.