Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number A17-18 found under Valve Regulating Fluid Pressure by Conoflow Regulators And Controls. The National Stock Number assigned to this part is 4820013193761, 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 A17-18.