Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 3 4-1028(F11 found under Valve Globe by Btr Valve Sealants Inc. The National Stock Number assigned to this part is 4820014395084, 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 3 4-1028(F11.