1. The indoor/outdoor refrigerator thermometer wireless temperature range: Indoor -10℃-60℃ (14℉- 140℉), Outdoor -40℃-60℃ (-40℉-140℉) and the transmission range is 100M/328ft(open area). You can use it in the fridge, freezer or outdoor, which provides safe food storage. 2. Audio Alarm: The wireless freezer thermometer Alarm console includes audible and visual alarms when temperature exceed your pre-set minimum and maximum alarm settings.After setting the alarm temperature, a short on the alarm button screen show an "alarm" , and the set alarm function be turned on by default. 3. Easy to Read Display: The freezer thermometer has LCD screen with large digit.Records Min and Max temperature provides the historical temperatures readings. With this feature, you can easily monitor the temperature change of your refrigerator and provide double protection to your food safety. 4. Multiple Installtion Ways: The wireless thermometer with alarm is easy to install. The display unit can stand on the table, hang , magnet on the refrigerator. The wireless sensor can clip on door or hang . Note: Don't put this product in the place where it is hot, humid, dusty or full of gas, in case that its electronic components are . Colour:White Material:ABS Package Contents: 1 * receiver (using 2 x AAA batteries, without batteries) 2 * transmitters (using 2 x AA batteries per transmitter, without batteries) 1 * English instruction manual 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.