Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 1089-87 ITEM 6 found under Valve Regulating Fl by Insinger Machine Company The. The National Stock Number assigned to this part is 4820014307303, 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 1089-87 ITEM 6.