Features: 1.Indoor and outdoor temperature LCD display digital room thermometer 2.Indoor and outdoor humidity display wireless hygrometer 3.Indoor temperature range: -9.9~+59.9C; outdoor temperature range:-20~+69.9C 4.Temperature accuracy +/-1.5C under working temperature 0-50C, resolution 0.1C 5.Relative humidity range: 20%~95%, resolution 1% 6.Records Max/Min temperature and humidity (indoor and outdoor) 7.Comfort level indicator 8.Low battery indicator 9.Time display in 12/24h 10.White backlight will lit for a few seconds after you press light button on top 11.Main unit can be matched up to 3 remote sensors(if you need more wireless sensors, you can visit our store for more sensors.)The CH button on screen is for switching channels. 12.Postion Method: table standing or wall hanging 13.Main unit: powered by 3xAAA batteries (Not included) 14.Remote Sensor: powered by 2xAAA batteries (Not included) 15.Battery Life: 3~6 months NOTE: For channel matching, you need to power on the main unit first. Then load batteries for remote sensor and turn the sensor to the channel you want to match(channel switch button is inside the battery compartment). If you want to manually update or reconnect the matched display on screen, you can press and hold the CH button on screen, and the data will be cleared. Specification: Item Size: main unit: 5.59”Lx0.87”Wx3.78”H(142x22x96mm) Sensor: 2.36”Lx1.06W”x3.78”H(60x27x96mm) Net weight: 260g Package weight: 300g Color: Black or White Package List: 1x B317 In/out Weather Station 1x WIRELESS SENSOR 1x Instruction Manual