The RUTA pump systems described here are vacuum pump systems consisting of Roots vacuum pumps from the RUVAC series in combination with a fore vacuum pump. They have been designed for rough and medium vacuum operation, i.e. for the pressure range from atmospheric pressure down to 10-4 mbar (7.5• 10-5 Torr). On the intake side RUTA pump systems consist of Roots vacuum pumps. Further compression to atmospheric pressure may be performed either by oil-sealed or dry compressing vacuum pumps or Roots vacuum pumps with pre-inlet cooling.