XIANQI Product description:Material: ABSColor whiteWeight: 0.178 kgIndoor temperature range: 0 C to 60 C (32 F to 140 F)Outside temperature range: -40 C to 60 C (-40 F to 140 F)Power supply: 2 x AAA host batteries, 2 x sensor AA batteries (not included)Package includes:1 * host2 * sensorDescription:Two wireless sensors - the refrigerator thermometer can show the temperature of the base and the sensors at the same time.Accurate Max / Min Recording: Indoor: -10 C ~ 60 C (14 F ~ 140 F); Outdoor: -40 C ~ 60 C (-40 F ~ 140 F); Transmission range: 100 m (open area). It can record the maximum and minimum temperature and display up and down and parallel arrows to show the trend of the current temperature.Audio alarm - The wireless refrigerator temperature with audible alarm, you can set the maximum and minimum alarm value manually. The bell can ring when the temperature value reaches the maximum or minimum alarm value you have set.Multiple installations - the thermometer is easy to install. With built-in magnets, a hanging hole and a bracket on the back, you can place the main unit in the refrigerator door, hang it on the wall or place it on the table.Ease of use - There are 6 function buttons on the main unit, just press the appropriate button to turn the alarm on and off, turn on the Celsius or Fahrenheit and clear the Max / Min records.