Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number HU9975 found under Gage Ring Master Setting by Rollsroyce Airlines. The National Stock Number assigned to this part is 5220008403772, and the Federal Supply Class is 5220 Inspection Gages And Precision Layout Tools. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like HU9975.