Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 635020-01-4 found under Valve Actuator by Tri Tec Manufacturing Llc. The National Stock Number assigned to this part is 4820016008080, 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 635020-01-4.