This 16" bong cannon diffuser glass water bong strongly believes in the rule of three. First, as the name suggests, you get three barrels, each of which helps diffuse the smoke and make it much smoother. Then you also get 3 ice notches for that extra smooth touch. See, the temperature is the worst thing when you smoke up. The coughing fits and the damage caused to your health mostly comes from the hot smoke damaging you. The ice notches and the barrels cool down the smoke, making it less harsh on your system.