GRAV® Upline® Water PipeGRAV Upline Water Pipe The GRAV Upline Water Pipe is a compact and efficient smoking device designed to elevate your smoking experience. Here's what makes it stand out: Made on 38mm tubing for durability Vertical downstem catches ash, keeping the pipe cleaner Ladder perc restrictions create bubbler chambers to wash and filter smoke Upper chamber and angled mouthpiece function as splashguards Comes ready to use with a 14mm Octobowl Works best with