Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number M4-5-INCH found under by Pres Vac Engineering Ltd. The National Stock Number assigned to this part is 4820013464025, 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 M4-5-INCH.