Multifunction: The digital altimeter includes a digital barometer, weather forecast, time, calendar, thermometer and backlight. Upgrade: The revised second-grade outdoor altimeter generation cancels the compass (it is easy to measure the errors in the initial phase, and the error is a little big) and the altitude display is added. Now start measuring the altitude by itself 2 minutes later. You don't need to enter it manually. The original machine was entered manually. It has historical altitude pressure records and can store up to 256 records. Altimeter: The measurement range is -700 meters to 9000 meters (the altimeter can be used for the first test calibration.). The resolution is 1 meter or 3 feet. Weather forecast: Start predicting weather conditions in the next 12-24 hours. The effective range is between 30 and 50 kilometers. Altimeter Barometer: Designed for outdoor use, it is an ideal device for various outdoor activities. It can be hung on a backpack or belt for easy carrying. Press the button at any time to provide you with backlight.