Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 804 3 found under Screw Valve by Bureau Of Mines Helium Operations. The National Stock Number assigned to this part is 4820009633897, 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 804 3.