Double Diaphragm Pumps are designed for use in applications requiring large volume transfer in a short time . Driven by compressed air, these can transfer contaminated media & are very useful for cleaning out pits with mixed liquids such as oil, water etc. Ability to run dry: as there are no close fitting or sliding parts . Pumping efficiency remains constant: no rotors, gears or pistons that wear over time, hence no decline in performance.