Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number A40021 found under Spindle Counter Wei by Engineered Systems And Designs Inc. The National Stock Number assigned to this part is 3915009394661, and the Federal Supply Class is 3915 Materials Feeders. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like A40021.