The slanted diffuser is a pollen style CO2 diffuser that connects to CO2 injection systems to easily and uniquely disperse CO2 gas into the Planted aquarium. The elegant and low profile design of the slanted diffuser makes it ideal to minimize the visibility and intrusiveness of the CO2 injection system on planted tanks. The slanted diffuser has a 15 mm disc. Compatible with 6 mm (1/4") - standard Airline tubing. Suction cup included.