Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number S9553-CH-MMO-010 FIG 7-43-48 found under Valve Safety Relief by Pacific Consolidated Industries. The National Stock Number assigned to this part is 4820015887073, 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 S9553-CH-MMO-010 FIG 7-43-48.