Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 1284 found under Screw Rear Sight by O F Mossberg And Sonsincorporated. The National Stock Number assigned to this part is 5305010653170, 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 1284.