Easy to use. Charged my boat batter with no issues.I have purchased a few of these over the years; I have several batteries that sit idly for extended periods, but I need them to work immediately (without fussing with a jump) sporadically. I have not had any problems; they do what I need them to do, and they are less expensive than the 'popular' brand.I own other Diehard battery maintainers. They are earlier versions of this model, I think. I've owned other popular brands that were more expensive and not as functional. This is by far the best value for the money, as every one I own, some over seven years old, continue to wiork flawlessly while other brands have died. One thing that should be pointed out is the fact that this is not just a six volt unit. It will handle six or twelve volt batteries and will adjust itself to what it's attached to.This is my second one I bought. I use one to maintain the battery for my lawn tractor and the other for charging the battery that charges my RC model batteries in the field. No problems,---TomcatPerfect for keeping the battery topped up in an occasional use vehicle. Gone are the days when a trip in the convertible has to be canceled because of a dead battery. Great product and connection options for the price.This thing does the trick exactly as it is supposed to do. Works better than I thought it would for the moneyThe battery charger was shipped promptly, product was as advertised and undamaged and I have it currently doing a maintenance charge on my corvette's car battery when I don't drive it frequently as I should.I have only recently used the charger . It is the first time I have needed it. I think it is defective. The first time I used it, it would not charge the battery. It likely has been long enough that the company may not replace it or refund my money. It is hard to like something that does not work.Dave Giles