Air-Operated Double-Diaphragm (AODD) pumps are classified as reciprocating, positive-displacement-style pumps. They operate by displacing fluid from one of its two liquid chambers upon each stroke completion. To operate, the diaphragm pumps require a given amount of pressure and air volume to deliver the proper amount of fluid. The simple genius of the AODD pump design means that there are only a few wetted parts that are dynamic: the two diaphragms, which are connected by a common shaft, the two inlet valve balls and the two outlet valve balls. These pumps widely confirm to API 676, 3rd edition and are ATEX and CE certified.