The GRAV Gravitron 2.0 Bong has a new and improved design featuring glass five times thicker than previous Gravitron pipes. This type of bong creates big, efficient hits through gravity and pressure without any loss of smoke in the process. The upgraded grommet is made from platinum cured silicone and ensures a tight seal, while the flanged neck at the top makes it easy to lift the bottle. Harness the power of gravity while you take a rip! Each bong includes a 19mm male herb slide.