Received today. First I read the instructions. There are no pictures in the instructions. It does not specify which end of the device to connect the air hose to; So I tried it both ways. (I know the Revain photo shows the correct ending). I tried pumping air into two different car tires that were almost full before my attempts. The device completely blew them both away. His battery was fully charged. I even stuck it in the wall when I tried it. It's already back in the box and my return label has been printed. The instructions are so badly written that I don't want to exchange the device (assuming it's defective). I'll just order a completely different tire pump.