Ainiwo Silver 6 In 1 Multi Function Hiking Digital Altimeter /Compass /Barometer /Thermometer Stylish and Precise Low battery indicator; Powered by 1 CR2032 3.0V Lithium Battery (Included) 6 in 1 Multifunction: Altimeter, Barometer, Electronic Compass, Thermometer, Weather Forecast and Time Display. Portable and Lightweight. Easy to use, easy to carry with the detachable neck strap. Ideal and oecumenical for outdoor enthusiasts seeking extreme performance technology