Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number PR11-04BSS found under Valveregulatingfluid Pressure by Parker Hannifin Ltd. The National Stock Number assigned to this part is 4820016937189, 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 PR11-04BSS.