Worked really nice for three years, then it broke for no good reason. I'm not impressed. I also found the indicator lights overly complicated. Found myself constantly having to refer back to the manual to see exactly which lights meant what. Additionally, this charger was touted as having the potential to restore batteries that were kind of shot. Not once did I find this charger able to restore a battery that was dead. I wasn't expecting miracles, but I seriously don't think that the desulfating feature really accomplished anything. This charger seemed really just equivalent to a battery charger that was much cheaper and less complex. Would not buy again.

I am very happy with the product. I have a motorcycle that I take her for a walk a few times, and generally I have to go down to the parking lot of the building once a month to turn it on and so the battery does not discharge. However for different reasons I could not do it in 3 months, it was very cold in my city and the battery is over. This product helped me to revive it in a few hours and I no longer have to worry about going down every 1 month to do it because I have it connected directly to the battery. It's excellent. Nor does it generate heat, the device stays cold and is low-power.

Seriously, this thing is amazing. I swap out deep cell marine batteries from my electric fence. This keeps them both in flawless shape. Fabulous product. Don't throw away the manual, however, because it has about 4000 modes to protect your battery, and unless you can memorize 4000 light combinations, you want the manual to decipher the readout.

About 20 years ago, I bought myself a TecMate OptiMate 3 (sold at the time under the Motion Pro brand), because it was the best battery-tender device available at the time to maintain a motorcycle battery.

20 years on, the OptiMate 3 has developed a fault and doesn't work properly any more, so I updated to an OptiMate 6. And it's better. It's smarter and more capable than the OptiMate 3, and now has a fast-charge mode as well.

The OptiMate won't replace a start cart. It can't put out that much current. But that's not its job. The Optimate's purpose is to test, charge, maintain and troubleshoot lead-acid batteries, including recovering heavily sulfated plates, and it does that well. It works with all types of lead-acid batteries "” standard wet-cell, AGM (advanced glass mat), and gel cell. (*DO NOT* try to use it for lithium automotive batteries, though. They require special chargers.) If you have a motorcycle, an ATV, a snowmobile, a boat, anything with a lead-acid battery that gets used infrequently and you need to be sure the battery doesn't go south during the off season, this is the tool for the job.

This thing is awesome, I had installed a brand new AGM battery in sailboat undergoing restoration a year ago, only thing hooked up to it was cabin light using LED bulb, battery held its voltage all that time and then I installed audio system, marine radio and fish/depth finder.
In the course of few days I plaid the FM radio for total of about 1 hour which depleted battery to 7 V, radio would no longer turn on and even cabin light looked like a candle.
I hooked up Sears charger claiming to be adequate for all types of batteries, 48 hours later voltage has not changed at all, dead, I thought my battery was shot before even getting chance to use it.
OK, now Sears charger claimed to be good for all types of batteries, probably meaning batteries made in Mexico, Brazil, China and so on but not including their own "AGM Silver" deep cycle marine battery, even though picture of boat is on the box.

This charger was hooked up for 72 hours, charged my battery back to 12.5 V in few hours then did the testing and all completed as described in manual, including sporadic charging as I played the radio for a while in two instances.
I don't want to have it hooked up at all times but knowing that it can recharge the battery in few hours is great, I have a solar panel that gets the job of maintaining voltage once the boat is out of garage and ready to sail.
Being equipped for worldwide electrical systems is another plus, I am very pleased with the product.