Lack of information for installation and use as the type of battery that needs plugging in (slow discharge). But despite this, it's a great product and value for money. Note that the cables are really too short (1 meter long). Can be connected over a soldering iron, a drill, however not enough power to connect a vacuum cleaner or a 1800Watt 1500Watt hairdryer. These devices require electrical capacity at start doubling their power and exceeding the continued ability of the transformer (2000W). But just find a little less powerful devices and this should work very well.