Enhance the look of your landscape while providing advanced aeration with the 20 ft. Customized Powder Coated Steel Underwater Aeration Windmill. Available in a variety of solid powder coated colors this windmill features a blade diameter of a full 73 inches. It can produce up to 4.5 CFM of air up to 30 psi for ponds or lakes 10-30 feet deep. Add your own logo or keep it simple with color options of Blue and White Bronze Forest Green Green and Yellow or Red and White. Includes 5-year warranty on all bearings and cams.