All have an elastic waist with working drawstring and are made in cotton jersey.  Jersey PJ Bottoms ( Nautical Whales, Music Notes) Extra comfortable relaxed fit. . Comfortable cotton jersey. Sleep Leggings (Camoosflage, Mama Bear) Sleep leggings have cuffs at the bottom so don't ride up your legs in bed! Refer to the size guide below, our experience is that sizing is generous and also there is plenty length in the bottoms. Moose on Red and Black Bears now go to a XXL.  https://www.hatley.com/en_us/customer-service/size-guide   Sizes: XS - uk 6-8 S = UK8-10 M = UK12-14 L = UK16-18 XL = UK20-22