1. This equipment is an equipment for outdoor sports enthusiasts. 2. Provide outdoor sports enthusiasts with rich and accurate information, such as electronic altimeter with backlight (weather forecast + altimeter + compass + barometer + clock). 3. Functions: altimeter, barometer, level, weather forecast, compass, thermometer, calendar, time, backlight. 4. Scope of application: Hiking, camping, mountain climbing, and other outdoor places. Batteries:2 x AAA batteries (not included) altimeter: Measuring range:-700m-9000m(-2300-2950ft) (initial test can calibrate the altimeter) Resolution:1 meter or 3 feet barometer: Measuring range:300mbar to 1100mbar Resolution:0.1 mbar. Electronic compass: 8-azimuth mode display External magnetic field correction Accuracy:3 degrees Resolution:1 degree thermometer: Measuring range:-10 - +60 (, optional) Resolution:0.1 degree Weather forecast and time: Weather forecast 12 to 24 hours from now 4 weather conditions:sunny - semi-clear - cloudy - rainy 24 hour clock Electronic backlight:5 seconds high brightness blue LED electronic backlight Colour:Gray Material:ABS Package Contents: 1 * Altitude measuring instrument Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.