Product parameters Electronic altimeter (Weather Forecast + Altimeter + Compass + Barometer + Clock + Level + Calendar) Blue backlight 8 in 1 Function. Size: Approx. 9 x 5 x 2 cm. Measurement range The measurement range is from -700m to 9000m (the altimeter can be initially calibrated), with a resolution of 1 meter. Barometer: The measurement range is from 300 mbar to 1100 mbar, with a resolution of 0.1 mbar. Electronic compass: 8-Azimuth mode display. Thermometer: Measurement range -10C. ~ + 60 (and units optional). Outdoor equipment This electronic thermometer is an ideal and simple choice for outdoor enthusiasts, and the detachable power cable makes the digital compass a perfect handheld device for various outdoor activities. It provides you with backlight when you press any button at any time. Power supply The handheld altimeter is powered by 2 AAA batteries (not included), which can be used continuously for a long time and is very practical. Wide application The electronic GPS navigation altimeter is suitable for outdoor places such as mountaineering, camping and rock climbing. Note: The altimeter should not be used in wet environments.