Designed to protect your delicate lashes while you get your beauty sleep. Made from 100% highest grade (6A) long fiber mulberry silk with a thickness of 22 momme and 100% PU foam filler (exclusive of elastic and piping) The Sipsilk Difference:: Slip pure silk products are made using slipsilk, developed and refined for over ten years to provide the ultimate combination of shine, thickness, softness and durability. In laboratory testing, slipsilk pillowcases were shown to absorb significantly less face cream than cotton pillowcases*, so they can help keep your skin’s moisture and valuable face and hair products where they belong, on your face and hair. Slipsilk was also shown to create 43% less friction on average*, which can reduce stretching and tugging on delicate facial skin. *On average compared to cotton pillowcases with a 220-360 thread count. Use up to 8 hours daily for maximum results. Care Instructions