I had one for a while they seem to be an OK unit. You will need at least 4 ga welder cable to connect it to your battery(s). IF it is a long run from the battery to the unit then you might need even larger cable.. If you don't have a battery or need to replace what you have I would recommend a pair of 6 volt "golf cart" batteries wired together for 12 volt.. I keep my system charged up with a solar panel.
2004 Chev Silverado Duramax optioned past the max. 2009 Jayco Eagle 308 RLS 765 watts of solar, 6-6 volt batteries (696 amp hour), 2000 watt (4000 surge) whole house inverter.
140 days boondocking in 2016
211/2015, 196/14, 247/13, 193/12