After using several of the Gallagher and other top name solar fencers I now use the inexpensive 12v fence chargers with any 12v battery and an inexpensive solar panel. It is more economical to use separate components than the self contained units. The ones I have used in the past had batteries that didn't last long and if the power module burned out it cost as much to replace as a good 12v unit. Have one on a fence now with a lawn mower battery and small Harbor Freight solar panel that has been going good for several months with very little attention.