Usage Tips:Features: Multifunctional Digital Altimeter: it has the functions of weather forecast + temperature meter + altimeter + compass + barometer + clock + level gauge + calendar. High Accuracy Altitude Meter: the principle is to measure the height difference by the sensor sensing the change of atmospheric pressure. Clearly LCD Display with Electronic Backlight: with 5 seconds high brightness blue backlight. Weather Forecast and Time Function: forecast the weather conditions in 12 to 24 hours, 24-hour time format. With 4 Kinds of Weather Conditions: sunny, semi sunny, cloudy, rainy. Easy to Use: a simple equipment to provide necessary and accurate information for outdoor enthusiasts. Specifications: Material: ABS Altitude Measurement Range: -700~9000m (-2300~2950ft) Resolution: ±1m Barometer Measurement Range: 300~1100mbar Resolution: 0.1mbar Electronic Compass: 8-azimuth mode display, external magnetic field correction, accuracy: ±3 degrees, resolution: 1 degree Temperature Measurement Range: -10~60 (/ units switchable) Electronic Backlight: 5 seconds Power Supply: 2 * 1.5V AAA battery (NOT included) Item Size: 90 * 50 * 20mm / 3.54 * 1.97 * 0.79in Item Weight: 50g / 1.76oz Package Weight: 60g / 2.12oz Package Size: 15 * 8 * 2.2cm / 5.91 * 3.15 * 0.87in Packing List: 1 * Digital Meter 1 * Lanyard