Vector Informative - Don't Buy
I always keep a good portable 12 volt jumping system at my house. Not only are they great when we lose battery power in our main cars, but I have a boat and a few collectible autos that certainly are susceptible of not starting after sitting for awhile. I also make sure the unit I have has a built in compressor for low tire emergencies and other inflatable conveniences. My previous one was too old and the unit could no longer hold enough charge to start a dead vehicle. I couldn't find a replacement battery for it, so I requested a new one as a birthday gift a few months back, and this is the one I was given.
If you're in the market to pick up a portable jump starter, don't get this one. First off, the compressor, which never worked well (15 minutes to inflate a tire by 5 psi), just went completely. Second, while it will start a car, it has a unique feature that instead of having a switch that charges the jumper cables once they are hooked to the dead battery to be jumped, it activates itself once it feels the voltage from the dead battery and assures the jumpers aren't crossed. So when we left something on in the car and drained the battery stone dead, this thing wasn't any help because there wasn't enough juice in the battery to be jumped to activate the units flow switch. I had to actually take a trickle charger and somewhat charge the dead battery first before I could get this to start it. "In my opinion", this is an absolutely ridiculous design, making the thing useless in an emergency where someone left their lights on or the like. My tips for getting one of these instant power packs-first don't buy this one or any that require the battery to be jumped to have at least 2 volts available still in it. Get one with the switch and just be careful hooking up the cables. Second, see if you can find one that offers replacement batteries. They do get old and it helps save money than throwing the whole thing away. 3. Get one with a compressor.