Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 48-00-42 SHEET 33 found under Seat Valve by Huntington Ingalls Incorporated. The National Stock Number assigned to this part is 4820011471165, 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 48-00-42 SHEET 33.