Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number PPS-AD4138-7 found under by Watson Machine Co. The National Stock Number assigned to this part is 3110006107085, 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 PPS-AD4138-7.