The first charger I used was a battery tender that was outputting 13.6

Disconnected and put it on a Battery Tender - same result

Haven't been using long enough to rate longevity, but most ATV batteries don't survive more than a couple years unless you baby them thru the winter on a battery tender intermittently.

only lasted 4 months with a battery tender

It is kept on a battery tender

The only reason I gave it 4 out of 5 Stars on the East to Install is because I run a Winch and a Battery Tender

Got it quickly , so far so good , been using a battery tender to keep a good charge, in the past I did not use a tender and every year I have to replace , this is the first Weize I ever tried hope it last longer then the others

My motorcycle is always hooked up to a battery tender for proper maintenance if I’m not riding

Battery works as it should, no idea about longevity yet.