Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number AC990 found under Muffler Exhaust by Ingersoll Rand Inc. The National Stock Number assigned to this part is 2990001259003, and the Federal Supply Class is 2990 Miscellaneous Engine Accessories Nonaircraft. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like AC990.