Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number ER783D121204 found under Tee Tube To Boss by Designed Metal Connections Inc. The National Stock Number assigned to this part is 4730000506850, and the Federal Supply Class is 4730 Hose Pipe Tube Lubrication And Railing Fittings. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like ER783D121204.