The Grav Labs Bates & Worm Outside Diffusion Pump Bubbler is another incredible design collaboration between Grav Labs, Steve Bates & Worm Glass. With its surprisingly high water line, this glass dab rig requires a big rip to get the pump going, but when you start hitting it, it’s as smooth as can be. How it works is, the water is pulled through the diffusion pump then the glass bead separates your hit into thousands of individual bubbles that move up into the mouthpiece. Unlike the Bates & Worm Standard Bubbler this pipe has the diffusion pump on the outside for a new and exciting look. It features a 5mm thick wall 14mm female domeless quartz nail.