HONEYPUFF Premium Active Charcoal Pipe Filter Suit for Metal Pipe or Natural Wood Smoke Pipes Accessories. 6MM, 9MM multiple sizes are available-activated carbon tube filter: can reduce harmful components in tobacco (such as tobacco tar. nicotine, etc.). Material: High quality activated carbon material, so you can use them without any concerns. Usage: activated carbon tube filter is used in many pipes. When installing, the blue mouth is opposite to the cigarette holder. Product features: disposable items do not need to be cleaned. The pipeline filter can not only condense water vapor, but also accelerate the exchange of smoke, and the drying effect on the pipeline smoke is very good. Extend the life of the pipe.