My GB is a thick plastic pitcher with a 2-liter bottle that fits perfectly inside. Using old bong pieces, i took a stem and bowl (metal) from a real bong that was long forgotten, and i used that. Also, i have this Oring type device around the stem where it connects to the lid of the 2-liter, to prevent and air leakage. also make sure if your using a bottle with a cap for you GB, to screw it on good before you try to pull it up to get suction :thumbsup: