Since the heater had already pulled the empty battery in my small car, so I bought a "Power Pack" for about 50 euros at the hardware store. I had not tuned, which is built a lot of joy - apparently cheap - battery was broken after a year, and the substitute of my battery also made it much longer. And jump-start could therefore not give, but the on-board battery recharge only in a few minutes something so that it then handed to start with sorrow and distress. As the Eufab Powerpack was offered as a lightning deal in November, I slammed. Even the external appearance is much valent than the crap thing from the hardware store. On rubberised grip it kannman keep well and wear. Also it can provide power, I find a nice feature. Whether I can do it again, I do not know. I had fully charged the power pack immediately after delivery again, and since then "slept" it in my car, which is not in the garage. Until yesterday, when someone asked me in a parking lot after jumper cables. And I could say "I've got something better!" and hope that it worked. Someone had forgotten to turn off the light on his car, it is just crisp cold, and the battery of the car was no sound more of themselves. We have clamped the stable terminal clamps, switch jumper to turned "on" key is pressed, the starter immediately turned really fast - and the engine was running within one second, and I was called "angels in shining armor". For the fact that the device was already two and a half months in the cold car, it has made his job really well, what more could you want? The tension was still after the action in almost 13V, I have downloaded it again and it is ready for its next use in the car. So it must be: You do not have to take care of it yourself, but you can rest assured that it works when you need it easily. That's me the price of more than double of value supermarket goods!