Sun Company Altimeter 202 - Battery-Free Altimeter and Barometer | Weather-Trend Indicator with Soft Leather Case | Reads Altitude from 0 to 15,000 Feet SOFT LEATHER CASE - Keep the altimeter protected with the included soft leather case. Belt loop and attachable lanyard are included with case. 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.