Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number MAS4421 found under Gage Headspace by Giat Industries Centre De. The National Stock Number assigned to this part is 5220003984110, 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 MAS4421.