Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 991000-021 found under Microcircuit Linear by Kaman Aerospace Corporation. The National Stock Number assigned to this part is 5962012095254, and the Federal Supply Class is 5962 Microcircuits Electronic. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 991000-021.