Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number CA4 A221-600 FS1 found under Switchrotary by Kraus And Naimer Inc. The National Stock Number assigned to this part is 5930016790862, and the Federal Supply Class is 5930 Switches. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like CA4 A221-600 FS1.