Description:This is a wireless digital freezer therometer. It can be used in the freezer and act as therometer indoor and outdoor. Its own audible alarm can warn you of the exceeded temperature in time.Features:The minimum and maximum temperature are display on the LCD screen and can be reset manually. With indoor and outdoor audible alarm. When temperature exceed your pre-set minimum and maximum alarm setting, it will make a sound alert. The easytoread LCD screen displays the current indoor and outdoor temperature. When the battery is low, it will be displayed on the LCD screen. Includes 24 hours Min and Maximum temperature records and you can easily monitor the temperature change of your refrigerator and provide double protection to your food safety. With a temperature trend indicator arrow and daily high and low information. Comes with a adjustable hook so the dispay is wall-mountable or stands upright for tabletop use.Specification:Material: ABSUpdate Rate: 10 secondsTransmission Range: 328 FeetIndoor Temperature range: 0 ~ 50 (32 ~ 122 )Outdoor Temperature range: -40 ~ 60 (-40 ~ 140 )Power Supply: 2 X AAA battery for the host, 4 X AA battery for the sensor (Not included)How to Install the Sensor:The sensors are equipped with a spring-loaded clips along with a Plastic grip to tightly attached to the edge of a shelf.The display is magnet-mountable on a fridge, or use the integrated keyhole for wall mounting.Package Included:1 x Host (Battery not included)2 x Sensor (Battery not included)1 x User ManualNotice:Do not install the reverse battery.Do not put the receiver near metal.Avoid transmitter directly in the rain..