Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number MODEL WLC 2-1 2IN found under Valve Check by Durabla Mfg Co. The National Stock Number assigned to this part is 4820012689841, 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 MODEL WLC 2-1 2IN.