Fangrui Product Details [simple To Use]:the Temperature Range For This Temperature Controller Is -40-110. Convenient To Set And Adjust, With Hd Lcd Display And 4 Buttons. It Is A Relay Temperature Controller, You Need To Connect Additional Power Supply For The Load. [high Current 30a Relay]: High Power: 220v 30a. It Is Can Be Used High Power Equipment, Like Refrigerator,brooder,incubator,fermenter, Greenhouse,etc. Connect Power Supply And Heating/cooling Equipment, Place The Probe And Set The Temperature, It Will Work Great. [heating/cooling Function]: Heating Mode H : When The Detection Temperature Less Than Equal Set Temperature - Hysteresis Temperature, The Relay Is Turned On, And The Heating Equipment Starts To Work; When The Detected Temperature Greater Than Equal The Set Temperature, The Relay Is Disconnected And The Heating Equipment Stops Working. The Principle Of Cooling Mode C Is The Same. [delay Start Temperature Correction Function]: Delay Start Oph: When A Heating Or Cooling Job Is Completed, The System Starts Timi