It has the function of controlling temperature and humidity at the same time. The current temperature and humidity can be displayed in real time. With over-limit alarm function. Relay work indication function. With power reverse connection protection function, the controller will not work when reverse connection. Specific Setting : 1. Set the starting temperature:Long press the S button for 3 seconds, the red LED D3 flashes, at this time the display shows the start temperature value, press the + and-buttons to adjust this value, long press to continuously adjust. After the adjustment is completed, long press the S button to exit or 10S no button to exit automatically. 2. Set stop temperature:Long press the S button for 3 seconds, the red LED D3 flashes, then short press the SET button again, the red LED D3 is on, and the display shows the stop temperature value. Press the + and - buttons to adjust this value. Long press That is, continuous adjustment. After the adjustment is completed, long press the S button to exit or 10S no button to exit automatically. 3. Set the starting humidity:Long press the S button for 3 seconds, the red LED D3 flashes, then short press the SET button twice, the green LED D4 flashes, the display shows the start humidity value, press the + and - buttons to adjust this value, long press That is, continuous adjustment. After the adjustment is completed, long press the S button to exit or 10S no button to exit automatically. Colour:As shown Material:Metal + plastic Package Contents: 1 * Temperature and Humidity Sensor Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.