Reminder:The video is the operation of setting heating: 30start, 34stop.Pre and hold the "SET" button, the adjustment shows "H", the green light is on, it means heating, the light is off and the heating stops. ZFX-ST3012 Dual Temperature Controller Thermostat Controller Temp Control Thermoregulator Control Module 12V/24V/220V Feature Microcomputer intelligent digital temperature controller with dual display and dual control function. Made of fine quality material with strong durability, long service life. Wide temperature measuring range from -50 to 110 and temperature control range from -50 to 110, high accuracy. Support cooling/heating mode setting and ultra high/ultra low temperature alarm function. Support delay protection function and temperature correction function. Easy setting, easy to install and use. Can be widely used in the greenhouse cultivation, aquatic animal husbandry, room temperature control. Specifications: 1.Model: ZFX-ST3012 2.Power Supply: 12V, 24V, 220V (Optional) 3.Material: Plastic 4.Temperature Measuring Range: -50~110 5.Temperature Control Range: -50~110 6.Temperature Measuring Accuracy: 0.5 7.Temperature Control Accuracy: 1 8.Working Temperature: 0-50 9.Storage Temperature: -10-60 10.Sensor Probe Cable Length: 1M/3.28ft 11.Item Size: approx. 76 * 55 * 31mm / 2.99 * 2.17 * 1.22in 12.Package Size: approx. 80 * 80 * 35mm / 3.15 * 3.15 * 1.38in 13.Package Weight: approx. 96g / 3.39ounce