Temperature compensated, aneroid barometer movement. Fully adjustable. Inch and millibar scales. Our standard barometer movements are calibrated for altitudes to 3,500" above sea level. The thermometer displays temperature in both Fahrenheit and Celsius on the left scale, and the hygrometer shows % of relative humidity on the right. * Maintenance-free, ultra-hard finish guaranteed to NEVER tarnish * Patented Slide-n-Lock™ Mounting System, no visible mounting screws, easy removal for adjustments & battery replacement * Weatherproof construction for outdoor use * Beveled glass crystal * United States Patent #7,293,456 * Lifetime warranty on finish and movement * Dimensions: Dial: 5 3/4” (145 mm) Base: 7 1/8” (181 mm) Depth: 1 7/8” (48 mm) * Weight: 1.45 lbs (658 g) About Weems & Plath Founded in 1928, Weems & Plath is a company steeped in the rich tradition of navigation. They offer a wide spectrum of precision instruments ranging from brass nautical clocks and barometers to binoculars and children"s books. The company"s dedication to providing the highest quality possible is evident in every step of the building process. From development to production, Weems & Plath strives to be meticulous and offer exceptional service. The rich history and high standards of Weems & Plath will carry on into the future. * The perfect outdoor barometer * Temperature-compensated, aneroid movements * Calibrated for up to 3500 feet above sea level * Tarnish-proof, waterproof, maintenance-free design * Features Slide-n-Lock mounting system * 145mm dial diameter