Line voltage thermostat has larger, more sensitive, bi-metal sensor that improves temperature accuracy to 3°F. This feature achieves a better comfort level with a reduced temperature swing as compared to economy models. Modem appearance with large knob for easy adjustments. No ground wire, making installation fast and easy. Clean, bevelled style suits any decor Sits flush against wall Includes °C and °F control dials Bi-metal sensing element. Operates 41 to 90°F. Mounts directly to a 2 x 4 inch vertical electrical outlet box. Fully vented cover allows air sensing in all directions. Large knob allows easy adjustment to all temperatures. Single or double pole (positive off) available. No ground wire design.