A pump assembly (100) having a pump housing (206 and 208) and a rotor (222) rotatingly disposed within the housing, the rotor having a plurality of slots (226). The pump assembly includes a plurality of vanes (224), each vane moveably disposed in one of the plurality of slots, and an input shaft (228) coupled to the rotor for applying a torque to the rotor. The pump assembly (100) also includes a prime mover (400) for generating a torque and a magnetic coupling unit (300) for magnetically transferring the torque generated by the prime mover to the input shaft. The vanes may have a leg (256) which extends radially inward from a blade (254). The rotor and input shaft may be integrally formed.