Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 4166 found under Stem Hanger by Little Giant Pump Co. The National Stock Number assigned to this part is 4820007531320, 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 4166.