Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 2520A found under Spider Universal Joint Vehicular by Zeller Corp The. The National Stock Number assigned to this part is 2520008905944, and the Federal Supply Class is 2520 Vehicular Power Transmission Components. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 2520A.