Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number A300-250-50 109 found under Bushing Sleeve by Environmental Technology Inc. The National Stock Number assigned to this part is 3120013559771, 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 A300-250-50 109.