Altimeters indicate altitude, measuring the static atmospheric pressure, which decreases with the altitude.
When an aircraft changes altitude, the aneroid capsule responds to the pressure change and through a linkage and a geartrain moves an instrument's pointer. The capsule has a very stable elastic characteristics to ensure accurate readings. A bimetallic compensation eliminates the effects of the temperature changes.
Our altimeters are precise, temperature compensated, shock and vibration resistant.