Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number MV50 28 2 0311 S503 023 MBKSSEO3 found under Valve Ball by F S Welsford Company. The National Stock Number assigned to this part is 4810015460198, and the Federal Supply Class is 4810 Valves Powered. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like MV50 28 2 0311 S503 023 MBKSSEO3.