1.Wireless signal transmission distance without interference 100 meters, can display two different maximum and minimum temperature records at the same time.<br> 2./F unit conversion: Celsius and Fahrenheit display can be switched to meet and has strong signal penetration.<br> 3.ALARM SETTINGS: When the indoor or outdoor temperature exceeds the preset minimum and maximum alarm values, the thermometer will emit an audible alarm and a visual alarm to alert you and allow you to see if adjustments are needed.<br> 4.EASY TO INSTALL AND OPERATE: Use the magnet on the back to magnetically attach the thermometer directly to your refrigerator or freezer, or place it on a table.<br> 5.APPLICATION: Can be used in the refrigerator, freezer or indoors and outdoors to easily monitor temperature changes and provide double protection for your food.<br> Parameter:<br> Measuring range (transmitter): -40~60 ( -40~ 140)<br> Tolerance: 1 ( 2 )<br> Temperature Resolution: 0.1<br> Wireless Frequency: 447.6MHZ<br> Wireless range: 100 meters without obstacles<br> Main unit size: 95x62x20mm<br> Transmitter size: 95x36x20mm<br> Use of power: (default delivery without batteries)<br> Host: 2pcs 7 batteries (AAA)<br> Transmitter: 2 pcs of 5 good batteries (AA)<br> Colour:White<br> Material:plastic<br> Package Contents:<br> 1 x Thermometer<br> 2 x Transmitter<br> Only the above package content, other products are not included.<br> 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.