Percolator bongs offer the smoothest, coolest hits possible by filtering smoke before it reaches your lungs. Instead of simply being filtered through water like a plain bong, percolator bongs feature an added piece called percolators or “percs” for short, which diffuse your smoke into tinier bubbles. These bubbles greatly increase the surface area over which smoke travels through the water, giving it more time to cool and filter out impurities. The result is a cleaner and much smoother toke with a difference you can taste.