The beautiful chrome atlantis barometer is highly reliable. It has a 4" dial, a 5.5" base and is 2.88" deep. It comes temperature compensated with aneriod movement. The scales on the barometer are inch and millibar. This barometer's movements are calibrated for altitudes to 3500' above sea level. Movements for altitudes from 3,500' to 7,000' are available by special order for an additional charge. The barometer weighs 3lbs. 3oz. The fine chrome plating on the solid, forged brass case adds timeless depth and luster to the exterior, while the precision movements used inside maintain the traditional quality expected from any instrument carrying the Weems & Plath name. The screw bezel allows easy access to the components when the unit is mounted. It comes with complete instructions, mounting hardware and a limited lifetime warranty.