Drop Hammer Type Exhaust Fan  Mainly used for greenhouse, industrial workshop, livestock housing; Low noise and high air flow capability; Blades:  6 pcs of BA 430 stainless steel. Thickness: 1.2mm Blades can clean themselves automatically when they are running; High efficiency motor with stable performance.  1380*1380*400 mm * The normal delivery car can’t take it Because of the volume of the product,  please chose for 3-6 days delivery or Shop pick up