Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 83553-78X5 PIECE 7 found under Pad Bearing by Electric Boat Corp. The National Stock Number assigned to this part is 5342012133777, and the Federal Supply Class is . Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 83553-78X5 PIECE 7.