Man, thats a broad question. Theres tons of them out there along with a boatload of information... They all basicly do the same thing, just depends on how much you want to spend and how elaborate you want to get... Im fixing to install one on my 65 and it uses a 5 pound cylinder, Milwuakee guages/selenoid switch and holds about 12 pounds of media. Search online, theres all kinds of info...