Features: Adopt super-accuracy sensor from Swiss. Incorporates GPS, altimeter, barometer, compass functions, etc. Thermometer, hygrometer, time, date, alarm clock. Altitude total gain/loss, 24 hours altitude record and chart. Max/min altitude, temperature, huminity record. 24 hours air pressure trend chart. Built-in rechargable battery. LCD backlit and LED torch. IPX 4 waterproof. (Do NOT submerge in water.) Functions: GPS Course Return: Direction, distance, speed GPS course return selection Altimeter: Altimeter range(-700 to 9000m/-2296 to 29500ft), with 1m/feet accuracy. Max./Min. memory for altitude. Altitude history and graphical display of the last 24 hour altitude readings. Altitude total gain or loss: 44999 meter/feet range. Sea level altitude setting. GPS distance, speed, erect ascending/descending rate, course return record. Barometer: Pressure range 300hpa to 1100hpa(8.84inHg to 32.44inHg) Resolution of 0.1hpa(0.01inHg) 24 hour pressure history and graphical display Electronic pressure weather forecast(sunny, slightly cloudy, cloudy, rainy) Pressure trend indicators Sea level air pressure setting. Compass: Direction Angle Thermometer: Range from -20 to 60 (-4 to 140) and selectable Max./Min. memory for temperature Hygrometer: Relative humidity(20% - 95%) Max./Min. memory for relative humidity Time: Hour, minute, second Year, month, day, date Alarm clock Time zone setting Specifications: Material: Plastic Dimension: 10 * 6.5 * 2cm / 3.9 * 2.6 * 0.8in Weight: 75g / 2.6oz Package Size: 15.8 * 11 * 3.5cm / 6.2 * 4.3 * 1.4in Package Weight: 126g / 4.4oz Package List: 1 * Altimeter 1 * Charging Cable 1 * Wrist Strap 1 * Cleaning Cloth 1 * User Manual