Size: One size fit most Our silk hair bonnet are handmade in small batches in Perth, Western Australia from the finest 100% mulberry silk fabric. It is hand-crafted Silk with natural dyes (Non Toxic Dyes). Silk has a soft subtle feel that is gentle and provide a number of hair and scalp benefits that helps maintain and revive your hair keeping it soft, hydrated and less frizz. It is great for use with overnight hair treatments. We use double layered silk fabric meaning more hydration, more benefit for the hair and more durable. They are very comfortable with stretchy elastic band and it is cut to fit as many adult head as possible. It also makes a fabulous gift.