On-board air is a handy thing to have on the trail. Being able to patch and re-inflate a tire on the trail is much easier than actually changing a tire. With on-board air even re-seating a tire bead isn't a big deal. Forget about airing up tires, imagine how nice it would be to be able to run air tools on the trail for repairs? Generally you have three choices, a CO2 tank, an electrically driven compressor, or an engine driven compressor. Now CO2 tanks aren't necessarily cheap, have a limited capacity, and cost money to be filled. Typically they do have enough capacity to seat a tire bead, or re-inflate your tires after a trail ride. However its just a storage tank once its empty is empty. Most of the time a renewable air supply is a better choice, which leaves most people with the choice of a engine driven setup or an electric setup. Now when I say electric compressor, I'm not referring to those things you plug into a cigarette outlet, with those, you might as well be using a bicycle pump. When I say electric compressor I'm talking more along the lines of a PUMA unit. Extreme Air, and Oasis are also major names in the electric OBA market, but typically cost more. These electric units are easy to hook up and work even when the Jeep isn't running. These larger electric units typically will run air tools, but typically not continuously. This is where the engine driven compressors accel. Most A/C compressors are designed to be lubricated by oil that is carried by the freon in the system. York A/C compressors however are different, they have their own oiling system. Think of the York as a mini engine, oiling system, crankshaft, pistons and valves, its all there. Since the York is self-oiling it works great as an on-board air setup. A York compressor will keep up with air tools, the only real downside is that the Jeep has to be running to use it, so if you break down, you lose the use of your OBA, and air tools.