Mighty Mule Automatic Gate Opener for Heavy Duty Single Swing Gates for 18 Feet Long or 850 Pounds (FM500) The FM500 is rated the Best in Class for Heavy Duty Gate Operators. Mighty Mule's strongest single swing gate opener for gates up to 18 ft. long or 850 lbs. Perfect for all gate types including ornamental, chain link, tube, panel, vinyl and wood. Easy DIY (Do It Yourself) installation that includes an interactive DVD for added assistance. All-inclusive kit that does not require welding or an electrician. 30% Residential Energy Efficient Property Tax Credit available! Residential home owners can use this credit on a new operator system, accessories and installation with the purchase of a Mighty Mule 10-watt Solar Panel (FM123). Backed by an 18 month Mighty Mule Warranty and Technical Support.