FEIN Turbo Cooling Technology uses a dual fan motor to prevent electrical damage and extend the life of the motor. One fan is sealed and creates suction to draw in air and debris, filter it and exhaust it. The second fan draws cooling air from outside and across the motor. This technique, typically found on more expensive vacuums, ensures the motor will never be starved for cooling air or exposed to the dirt and grime in the tank even if the hose and filter are blocked.