Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number ERK4530 found under Duct Upper Air by Optex Systems Inc. The National Stock Number assigned to this part is 2805004880729, and the Federal Supply Class is 2805 Gasoline Reciprocating Engines Except Aircraft And Components. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like ERK4530.