Compact and useful! Inflate RV tires slowly, but it works. I needed a 110psi pump and this is it! Connects to battery. You can use the connection cables as extension cables. (Do not use a "cigarette" power adapter for high pressure operation as this will blow the fuse in your car.) At high pressure in large tires it is about 2psi per minute. This is normal for emergencies. It's much faster on car tires that only require 35psi.