The Mighty Mule heavy duty dual, swing gate opener can open dual gates up to 18' long or weighing up to 850 lbs. per gate leaf. Works with chain link, tube, steel, ornamental and wood gates. Comes with a battery and has room in the control box for a second back-up or replacement battery (FM150). Designed for gates that open into or away from the property. 2 FM148 push to open brackets are required for applications opening away from the property.