Originally Posted by Lakers4Life
Do I want a Ball Lock or Pin Lock?
In leroy_sunset's post #87, that white plastic thing at the end of the hose is called a disconnect. They come in ball lock and pin lock versions depending on what type of posts are on the keg. When you put the disconnect on the input (gas) post, it opens the poppet valve in the post so you can fill it with air.
Technically, it doesn't matter which type you get so long as the disconnect and posts match. Coke kegs are pin lock, Pepsi and everyone else used kegs with ball lock posts.
Practically, it seems like used ball lock kegs are more common in the marketplace. I've also seen used pin lock kegs retrofitted to be ball lock. The little ball bearings in my ball lock disconnect work smoothly with my keg.