Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 55K4-101 found under Switch Thermostatic by Ellis And Watts International Llc. The National Stock Number assigned to this part is 5930013847835, 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 55K4-101.