1600 CFM (cubic feet per minute) heavy-duty roof mount attic exhaust ventilator. Galvanized steel construction. Suitable for 2400 sq ft (square foot) attic. 5.1A (ampere) thermally protected PSC (Permanent Split Capacitor) motor with built-in automatic cut-off. Includes 10A adjustable thermostat. Precision balanced aluminum fan blades for minimum vibration. 6-point suspensions (anchor points) for stability and high wind resistance. This fan requires minimum 600 sq in (square inch) net free area intake vent area. Suitable for up to 8/12 roof pitch. Includes galvanized steel mesh grill to protect against insects, birds, and rodents, yet allows adequate air intake. Easy installation with no special tools required. 5 year limited warranty on all parts.