Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number SP31609 found under Index Eyepiece Assembly by Cadillac Gage Textron Inc. The National Stock Number assigned to this part is 3460011380047, and the Federal Supply Class is 3460 Machine Tool Accessories. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like SP31609.