Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 2617-G1-MD89-1 found under Mounting Base Optical Tooling In by Brunson Instrument Company Inc. The National Stock Number assigned to this part is 4920010454546, and the Federal Supply Class is . Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 2617-G1-MD89-1.