Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 25-538 found under Ring Bearing Inner by Superior Fabrication Company Llc. The National Stock Number assigned to this part is 3110012899755, and the Federal Supply Class is 3110 Bearings Antifriction Unmounted. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 25-538.