Some rangehood brands offer offboard motor models. Off board systems do not house the fan and motor inside of the rangehood body as is typical of a standard rangehood, but instead opt to situate the motor either in the ceiling space, on the roof or on an outside wall.  The benefit of an off board motor configuration is that it allows the customer to enjoy the power of a large effective motor while being able to experience an overall quieter experience as the motors are further away from the cooking area.