Description: 8 in 1 Function: Digital altimeter, with digital barometer, digital compass, weather forecast, time , calendar, thermometer , and backlight. The device is based on the technology of electronic bearing sensor and barometric sensor The digital altimeter is designed for outdoor use, the detachable string makes the digital compass a perfect hand-carry device for various outdoor activates it will give you backlight when you press any button in any time. Altimeter : -700 ~ 9000m / -2300 ~ 29500ft Weather forecast History Altitude record : 256pcs records Compass: show bearing in degrees and cardinal point Thermometer : In ?C / ?F format Clock: In 12 hours or 24 Hours format Calendar Backlight Battery :by 2 x AAA batteries ( Not include ) Weight: 48g Size: 90 x 50 x 18 mm Package included: 1 x 8 in 1 digital altimeter 1 x Lanyards 1 x English manual