Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 40B021-3SM2 found under Semiconductor Devic by Drs Sustainment Systems Inc. The National Stock Number assigned to this part is 5961012938151, and the Federal Supply Class is 5961 Semiconductor Devices And Associated Hardware. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 40B021-3SM2.