Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 591-588AP found under Ball Valve Ported by Acme Products And Engineering Inc. The National Stock Number assigned to this part is 4820011693802, 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 591-588AP.