[SUB]john, always have the XLR running when you operate the top.
it will kill even a good battery in a few cycles with the engine off.
an old battery wont come back to life with a tender, it will be barely alive enough to start the car, and eventually it wont even do that.
if you get a new battery the tender will help you keep the newness for many more years
than you would get without a tender.
look into odyssey battery, i put a thread up here a while back about them, a bit more expensive, but alot more CCA and deep cycle capability
than the average battery.
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