They are like a tube with a spral thing inside, and a spring inside of that, and you wind it up when you put the balls in it. It holds 100 balls, takes no batteries, can be mounted on many places of the gun (not on top like normal loaders), and it does feed over 30bps. from the spring tension unwinding. You have other Q-Pods in your pack, and the one on the gun just screws off with a little turn and you can screw another one on. I"ve never used one but I saw a vid of someone reloading one in a game and he did it in like 2 seconds. I wouldn't get one though, my Reloader B is fine.