Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number TT 1A 250 R G found under Switch Thermostatic by Nason Company The Inc. The National Stock Number assigned to this part is 5930014523863, 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 TT 1A 250 R G.