Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number DIN7991M10X1.25X40-STL 10.9-B3B found under Screw Cap Socket He by Zelenda Machine And Tools Corp. The National Stock Number assigned to this part is 5305013074376, and the Federal Supply Class is 5305 Screws. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like DIN7991M10X1.25X40-STL 10.9-B3B.