Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number D2-554-1 found under Plug Machine Thread by Insinger Machine Company The. The National Stock Number assigned to this part is 5365013347172, and the Federal Supply Class is 5365 Bushings Rings Shims And Spacers. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like D2-554-1.