This is a remake of a fukuro obi into a Karuta Musubi style pre-tied obi (Obi締め/Obi cord not included). The material is unknown. I don't think it's silk. Obi width: Approximately 15.5 cm Karuta section: Approximately 37 cm Waist size: Up to 110 cm Set the Karuta section on your back, wrap the obi around your waist, and attach the end of the obi to the Karuta section using the pre-attached Velcro. Then, attach the included Velcro. We recommend using an Obi-jime (Obi cord). This is a handmade remake item. Please consider this before purchasing. Thank you for looking.