Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 4654 found under Stem E Main Valve by Spence Engineering Co Inc. The National Stock Number assigned to this part is 4820008856539, 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 4654.