Temperature Controller TD4-SNR + Solid State Relay SSR-40DA, PID Control For Heating/Cooling Over Accuracy: 0.2% Width switch power: 90-260V AC/DC Dimension: DIN: 1/16 (48WX48HX80Lmm) Range: -1999 to 9999 (depends on the input signal) Display: Dual display for Fahrenheit(F) and Celsius(C)