Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number PFRVA1 found under Valve Safety Relief by Barber Greene Co. The National Stock Number assigned to this part is 4820004386638, 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 PFRVA1.