Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 504S0018 found under Bearing Sleeve by Air Cruisers Company Llc. The National Stock Number assigned to this part is 3120002083682, and the Federal Supply Class is 3120 Bearings Plain Unmounted. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 504S0018.