Claw vacuum pumps series DHS are developed for industrial applications that need both vacuum and oil free air. That pumps are characterized by contact free working, no sealing fluid inside the body of pump, air cooling and energy saving. They are available with capacity of 360 mc/h and final pressure up to 150 mbar absolute. The working principle is easy: two claw shaped contact free rotors rotate inside the body of pump and suck air when they meet the inlet port. The reduction of volume between claws causes the compression of air and its discharging. Claw rotors are synchronized by gears. A centrifugal fan cools the body of pump. Contact free rotation of claw rotors causes reduction of wearing parts, reduction of maintenance and reduction of electric power consumption for pump work.