Autowit SuperCap 2 Battery-less Car Jump Starter, 800A 12V Portable Jump Box, No Pre-charging Needed, Built-in Supercapacitor for Extreme Heat & Cold

It works great, and you don't have to deal with a battery, since it uses capacitors. Easy to use and it only takes minutes to charge the capacitors. Then the capacitors will drain down in a few hours making it safe to carry around in a vehicle, until you're ready to charge it back again.

I have used this jump starter three times since purchase date. It worked perfectly when there was still some car battery left, but did not work when the battery was completely discharged. I knew this feature in the beginning, so I have not cancelled my road service insurance. I am pleased that this is one less thing that I have to remember to keep charged before using!

Started looking for a battery charger because of recent trouble with several vehicles and lawn mower failing because of weak batteries. I wanted something small and ran into this Autowit. It was interesting but I couldn't figure it out how it could use power from a discharged battery to start the same vehicle, What ever it works and is very light weight. You never have maintenance (such as keeping it charged) throw it in the car and whenever you need it you don't have to worry about it.

Have used with a variety of vehicles in a variety of weather conditions including to start a car in -25. Works very well and much easier to use than traditional cables. Would purchase again.

It REALLY works. As long as the dead car or pickup truck battery isn't COMPLETELY dead (just too dead to start the engine), the unit trickle charges itself off the dead battery, then floods the starter motor with electricity to start the engine. My only gripe is that like so many products in the last couple of decades, the markings on it are molded in, and it's hard to read black on black. My solution is to use a white or silver Sharpie (or paint marker) within the molded-in markings. Now they're easy to read!

Got my first chance to try out my new Autowit Supercap jump starter.  My neighbor asked if I could give him a jump start.  Well as it turned out that his car battery was completely drained, as it couldn't even wake up the % charge display on the Autowit.  So I took the Autowit off his battery and connected it to my own car battery just to charge it up.  Then took it back to his car and hooked it up again.  He turns the ignition key, and nuthin' happens.  Not eve  a weak murmur.  Puzzled I get my old jumper-cables out and hook up his battery to my car battery.  He turns the ignition key and instantly his engine cranks over and starts.  Now I'm left to wonder if this Autowit even works at all.  If it does, but, say, only if the car battery is not too badly drained,  the peace-of-mind I bought it for is simply gone.

Ads say that you do not have to recharge periodically. technically that is true but you do have to charge every time you will be using it. The difference is the way you charge it. If your discharged battery is too low in residual charge you will be left strande since this booster will NOT charge then,

The item seems like it works properly. My car battery appears to be completely dead and the jump starter gets the lights to come on and the ignition to click. Issue is that the jump starter doesn't hold charge between uses. So in the case that you're stranded you'd have to wait for it to charge off of your weak battery then try to jump your car with it. A friend of mine has one from a different company that holds charge and jumps the car without needing a charge each time like it seems this one does.

Try to use it when my battery died only to find the clamp lead doesn't want to connect to to the unit! So I was left stuck!

did'nt jumpstart my truck at least three times even though it seemed to be charged and was the correct capacity. barely got one crank