Specification: Material: ABS Color: Black Package Weight: approx. 94g Size: approx. 9 x 5 x 2cm / 3.54" x 1.96" x 0.78" Strap Material: Cotton Fabric Battery: 2 x AAA batteries (not included) 8 in 1 Function: Altimeter(Range): -700 meters - 9000 meters / -2300-2950ft (resolution ratio-1m/3ft) Barometer(Range): 350mbar-1100mbar (resolution ratio-0.1mbar) Digital Compass: show bearing in degrees and cardinal point Thermometer(Range): -10 Degree to +60 Degree, (Format ):°F/°C Weather Forecast: Start the machine, it can forecast the weather in the next 12-24 hours, the effective range of 30-50km LED Backlight: In any state, press any key to open the backlight, when open backlight, press any key to extend the time of 5 seconds Clock Format: 12Hr/24Hr (AM/PM) Battery: 2 x AAA batteries (Not Included) Package Included: 1 x digital altimeter 1 x rope 1 x manual Note: 1. Avoid use in rain, damp, too high or too low temperature (working temperature: 0℃-50℃, storage temperature: 20℃-70℃） 2. Avoid contact with corrosive material such as perfume, alcohol, cleaning agents and so on. 3. Avoid use in a area that maybe effect the magnetic compass normal use: Near the concrete/steel structures Close to power stations Close to home appliances (such as computer, TV, VCD, fax machines, speakers,etc) Close to the bridge which made from lots of steel or metal Close to the running vehicles (cars, trains, airplane) Near or on the surface of the metal plate