Peripheral discharge vacuum DC motors are equipped with a cooling fan on top of the motor that blows clean air over the motor to cool it. They have a design where air flows into the bottom of the motor and is discharged through vents in the motor. Since motors only use clean air to cool the motor, they are typically more reliable than thru-flow motors. Models have a high starting torque, operate at high speed, and create vacuum pressure and suction by a rotating motor fan. Motors are commonly used to move clean and dry air in commercial car washes, central vacuum systems, and extractor systems.