Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number SP8-4M found under by Sagana Instrumentation. The National Stock Number assigned to this part is 4820002620381, and the Federal Supply Class is 4820 Valves Nonpowered. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like SP8-4M.