Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number RK15F3M found under Repair Kit Valve by F S Welsford Company. The National Stock Number assigned to this part is 4820016122874, 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 RK15F3M.