Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number MCM 991-2 found under Microcircuit Hybrid by Q Tech Corp. The National Stock Number assigned to this part is 5962014401460, 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 MCM 991-2.