Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number MC1091A found under Semiconductor Devices Unitized by Microsemi Corp Massachusetts. The National Stock Number assigned to this part is 5961000796962, 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 MC1091A.