Wool... It offers comfortable use year-round due to its high moisture absorption and release properties, body pressure distribution and support due to its excellent elasticity, and natural functions such as high flame resistance and stain resistance. Size: 40cm, Thickness: Approximately 8cm (measured by an amateur) This is a sheepskin round cushion purchased from a co-op. It has been used infrequently and has no noticeable scratches or stains, but it has been stored at home for a long time (it was stored in a closet with futons and clothing, m(__)m). I haven't had a chance to use it, but I don't want to throw it away, so I hope someone will use it, m(__)m. Shipping will cost over 1,000 yen, so I cannot offer a discount, but thank you for your understanding. ^_^