Energizer M30Powers up to 20 acres or 5 miles of clean fence. With 0. 3 stored joules the M30 is ideally suited for small pastures and gardens. Gallagher's M30 Energizer has built in lightning protection and was tested under extreme conditions to ensure unbeatable reliability delivering outstanding performance day in and day out. WARNING: This product can expose you to chemicals including Styrene which is known to the State of California to cause cancer, and BPA