- Jul 11, 2001
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I can order them from Harbor Freight for $10 apiece, and I figure they may be worth it. I have two cars, one of which I only use maybe every 6 weeks, the other sometimes not for 2 weeks or more. I find that the batteries wear down just from running the cars' clock and whatever else might be a slow drain. I have a trickle charger I use from time to time, but it's a hassle to do that. The trickle charging solar units plug into the cigarette lighter. Of course, some days are sunny, some cloudy. I wonder if these things would do a good job of keeping my car batteries charged. My cars face north and I'm in Northern California, so I'd place them beneath the rear window. Anybody have experience with these?