Remixed and haven't printed or tested it yet. The concept is pretty much attach a little hose or something to the back part and use your own breath or maybe even some co2 power to shoot .68in paintball size ammo. Please be safe at all times...lol, but also have fun with it. I'd just attach the pb main piece to the arm cover via adhesive and make sure it stays. I'm sure ill update it to make it easier.