This digital refrigerator and freezer thermometer comes with remote sensors and can display indoor temperature along with one outdoor temperature at the same time. You can place the outdoor sensor outside or in a warehouse and record the temperature without leaving your home. Indoor temperature range is 10°C to 60°C (32°F to 122°F); outdoor temperature range is 40°C to 60°C (40°F to 140°F); transmission range up to 100 meters (328 feet) with no obstructions. The wireless refrigerator thermometer includes an audible alarm and lets you manually set maximum and minimum alarm values. It will ring when the temperature reaches your preset thresholds. When you first enable the alarm, there is a 10minute delay before it can trigger, to avoid immediate alerts on activation. The maximum and minimum temperature data are updated every 24 hours. There is no function to record or permanently maintain a history of max/min values, so these readings may not be retained long term. Use scenarios Home kitchen and garage monitoring: keep track of fridge and freezer temperatures from inside the house, with an outdoor sensor monitoring a garage or exterior storage area. Small business or cafe storage: monitor a display fridge and a backroom freezer or warehouse, helping ensure food safety and product quality with remote sensing. Outdoor storage or sheds: use the outdoor sensor to monitor temperatures in an external fridge or cold storage in a shed or covered area, while you stay indoors.