Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number PB53 found under Sprocket Wheel by Superior Equipment Co Buckeye Div. The National Stock Number assigned to this part is 3020002703503, and the Federal Supply Class is 3020 Gear Pulley Sprocket And Transmission Chain. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like PB53.