Hard buckram. Structured. Closed back. Stretch fitted. Silver undervisor. 8-row stitching on visor. Suitable for head circumf... Hard buckram. Structured. Closed back. Stretch fitted. Silver undervisor. 8-row stitching on visor. Suitable for head circumferences: S/M between 54 and 58 cm and L/XL between 57 and 61 cm.