Keep an eye on how your fridge is performing while also checking outside ambient temperature quickly and easily with the COMPANION Wireless Fridge Thermometer. With a digital LCD receiver and a wireless transmitter is easy to set up( 4 x AAA batteries are included) Pop the transmitter inside the centre of your fridge. With a wireless frequency and range of 25-30m/433 MHz, place the receiver in a protected area away from direct sunlight and allow approximately 30 minutes for both sensors to stabilise before an accurate reading within 1 degrees C can be taken. Allowing you to easily keep a watch on the Fridge / Freezer and outside temperature - and know that everything is as cold as you need.