A pure vacuum cleaner only for cars is limited to 900 W according to EU directives, in the household now it amounts to 1200 W. In addition to a mains cable, a vacuum cleaner can also have a battery or be connected to the 12V socket in the car. Mains, battery or vehicle voltage have in principle no influence on the power in W.

When buying, please exclude cheap plastic articles. It should already be a reasonable material and have enough suction power. Especially for pure vacuum cleaners with 12V connection, there seems to be a market for trash. What is meant here is not even the price, but material impression and suction, e.g. can also be above-average at the discounter's.

Particularly important in the car are the accessories, because here, the smallest crevices are not unusual. One can be glad if one can suck out again of these even screws and pieces of money. In systems without special bags it is not a big problem to use these again. Add to this the savings, if you do not have to change it.

As a further accessory, even rotating brushes may be provided, which may be effective e.g. in removing dog hairs sometimes, but not always. For pure vacuum cleaners, even the pressure side can be useful. Not to pump up the tires, but perhaps in the field of camping.

At the other end of the price scale there is, of course, the possibility to buy one cleaner for the car and the house. Either the device is not too bulky or stays out with a long hose, or it even consists of two parts (see video 2). Then it does not matter how far away the car is parked, because also the hand-held vacuum cleaner is powered by battery. However, permanently installing it in the car is then not possible.

Another advantage of this combination solution is the good processing. It is especially about the filters, washable or replaceable does not matter. The quality of the cleaning of dust is crucial, otherwise the finest particles are exhaled.

One thing, however, still applies to high-performance devices with rechargeable batteries: You should still ensure that a decreasing battery can be bridged by a permanently inserted cable and thus the power of the operated electrical device is maintained.

Finally, a warning. For many vehicles the ignition must be switched on to use the 12V socket. In addition, there is the daytime running lights then is constantly switched on. This can stress a recently more and more frequently weakening lead battery. So be at least shure that if the plug is disconnected, the ignition is switched off.