Sun Company AltiLINQ - Dashboard Altimeter and Barometer | Altimeter for Car and Truck | Reads Altitude from 0 to 15,000 Feet EASILY MOUNTS TO DASHBOARD - Mount AltiLINQ to either the top OR front of your dashboard in your car or truck. Comes with two hook-and-loop attachments so you can easily mount in two different vehicles. Quickly detach AltiLINQ and take with you on the trail. ACCURATE READINGS - Adjustable dial lets you account for high or low-pressure systems so that you get the most accurate reading possible. BATTERY-FREE - This analog altimeter is battery-free and simply adjusts based on the surrounding barometric pressure. EASY-TO-READ SCALE - Easily measure altitude up to 15,000 feet. Barometric pressure is measured in inches of Mercury (Hg). FULL INSTRUCTIONS INCLUDED - Easy step-by-step instructions help you learn how to set and adjust your SUN altimeter.