Description 4Pack Wireless Digital Thermometer Temperature for Refrigerator Freezer Fridge Specification Measuring Temperature Range: -20℃～50℃ (-4℉~122℉) Accuracy: ±1℃（±2℉); resolution: 0.1℃（0.2℉） Waterproof structure,level IPX3 Max/Min temperature value display on screen Stand for shelf or hang with hook; auto power on Operating voltage: 3v, CR2032 battery,1PCS Operations ℃/℉: Press °C / °F button to switch between Centigrade and Fahrenheit. ON : Press ON to turn item on. OFF : Press off to turn off , then it will turn back on, the clear/reset function. Note Replace the battery when the reading becomes erratic or the display clarity fades, using a button battery.open the screw and ABS shell, use new battery. Package included: 4PC Fridge Thermometer