This Twist bong features an unique twisted neck design design. It includes a slide with rubber grommet and is approximately 10" tall. Regarding the twisted neck, the fulcrum of the entire water pipe, it serves multiple purposes. The first and most obvious function of the twisted neck is the visual purpose. A twisted glass water pipe will make people do a double-take. You will be hard-pressed to find a bong whose neck is the centerpiece of the whole product. Furthermore, this twisted neck is useful for holding ice. To further cool the smoke before it is inhaled, place a bunch of ice cubes in the mouthpiece. The twisted neck will hold these ice cubes in place. As you inhale, the smoke will pass through these ice cubes and become much smoother. This bulbous chamber is capable of holding a sizable amount of water. Not only does the water filter your smoke, but it is also effective at stabilizing the water pipe in place. For diffusion, the 10" Twist Water Pipe is equipped with a diffused downstem. It works great and looks great.