Measurement temperature, the minimum memory/maximum temperature value. High temperature alarm (the temperature exceeds the preset value emit sound alarm), low temperature alarm (the temperature is lower than the preset value emit sound alert).<br><br>Indoor temperature range:0°C -+60°C Outdoor temperature range:-40°C -+60°C Temperature accuracy:+/- 1.0 Power (host):2 x AAA battery(Not included) Power (sub-machine):2 x AA battery (Not included) Wireless range:100 meters without interference. warn: Do not install anti -battery positive and negative poles. Avoid direct rain in wireless transmitters. If the sensor signal connection is interrupted, long the key to remove the button for 3 seconds to restore the signal connection. How to install outdoor sensors: Note: In order to receive the real temperature value, the sensor should be avoided directly in the sun. We suggest that the remote sensor is installed of the outdoor north. Before installing , book a screw, leave 5 mm from the screw head, and install the outdoor sensor on the screw. The electronic part of the outdoor sensor has a layer of moisture -proof synthetic resin to protect the circuit. However, the sensor is not waterproof, so it should be avoided directly rain. Sub-machine Quantity:B:2PCS Colour:As Shown Material:Plastic<br><br>Package Contents: 1 * host machine 2 * sub-machine<br><br>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.