Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number NL0258 found under Seat Valve by Dresser Rand Co. The National Stock Number assigned to this part is 4820007677209, 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 NL0258.