The Medium Gravitron from GRAV takes the classic gravity bong concept to a whole new level, with its all-glass build in a 9-inch version. Just like the Small Wide Base Water Pipe and Mini Round Base Water Pipe, the Medium Gravitron is made from thick borosilicate glass ensures maximum durability and performance, delivering powerful, efficient pulls with no waste. The way is work is: as the chamber rises, gravity and air pressure work together to draw the smoke into the bottle. Simply add water, load the bowl, ignite, raise, and enjoy! Perfect for solo use or group sessions, the originality and performance of the Medium Gravitron from GRAV deliver a unique and ultra-smooth experience.