Convenient as 12V (ideally camping, biking, Mattress) Too small (fits in the hand) capacity and thus low operating autonomy. Pressure too low to inflate a car tire without grill 12v engine as to achieve ie 4.5bars tire that would be 3.5bars it will take a time greater than 10 minutes allowed by the manual. So to top up on car opt for bigger, see tank for approx. 85 first prizes. For the rest we must be patient to inflate a large mattress 90x190 and cool 12v engine (or even the air piston).