ZoneIII
Supercharged
I have had at least 2 battery tenders go bad and still act like they were charging. You need to check their output voltage with them actually hooked to the battery. I now use nothing but a good Optimate on my bike and my generator. Here in Michigan the batteries are forced to be unused for 4-5 months. They do a way better job of maintaining and conditioning the battery. Pricey compared to some of the other chargers but worth the money. I also like the NOCO chargers as well. The NOCO Genius G3500 would be a good second choice. I use that on the 5th wheel battery.