Nason Temperature Switch TD-1C-220R. Factory-set TD Type Temperature Switch. Features set points from 140-300ºF (60-148ºC) | as well as a thermal snap disc that provides a nominal differential of 10 degrees. The factory-set TD Temperature Switch features set points from 140-300ºF (60-148ºC), as well as a thermal snap disc that provides a nominal differential of 10 degrees. Utilizes snap disc approach to sense temperature | High-quality snap-action switch | Factory preset | Shock and vibration resistant | Available in a wide range of configurations | Economical | NEMA 4, 13