Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 3984-3920 found under Bearing Roller Tapered by Tyson Bearing Co Div Skf Industries. The National Stock Number assigned to this part is 3110001005951, 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 3984-3920.