I purchased this a few years ago. It works really well. I usually help others jump-start their vehicle a couple of times a month, and even with heavy-usage like that, I still only charge it about once every 9 or 10 months... after about 15 to 20 uses and it is always ready to use. TRUE STORY: My Dad was at the bowling alley on a really-cold night and his truck wouldn't start when it was time to leave. A few people had tried to jump-start him with traditional cables but were unable to. Finally my brother-in-law showed up with a larger vehicle and larger battery, and they kept the cables hooked up trying to charge my dad's battery. I showed up about 20 minutes after this and pulled out this small-looking booster box and everyone looked at me like I was crazy... telling me that they had been trying to jumpstart and charge up my Dad's battery for the last 40 minutes, and they did not think I could do any better than them... especially with this seemingly small-looking booster box. Anyways, I disconnected the traditional cables and hooked up this box and within 3 seconds, my Dad's truck was started and he was good to go. That is a story my dad still mentions and laughs about many years later.
Rating: [5 of 5 Stars!]