SUNDERPOWER 8 In 1 Digital Multifunction LCD Compass Altimeter Barometer Thermometer 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 to 9000m / -2300 to 29500ft. Weather forecast. History Altitude record: 256pcs records. Compass: show bearing in degrees and cardinal point Thermometer: In Degree Celsius / Degree Fahrenheit Format. Clock: In 12 hours or 24 Hours format. Calendar. Backlight