Up Aqua’s CO2 inline atomizer is made of ABS plastic, which can handle higher pressures than standard glass diffusers. The atomizer hooks up in-line to the canister filter where CO2 is diffused through the fine ceramic atomizer tube, then atomized CO2 travels through the filter’s outtake tube. This is the most efficient way to deliver CO2 in large or high flow aquariums as it ensures proper CO2 dissolution. The atomizer is used with a 1/2″ or 12/16mm ID hose and atomizes CO2 at a working pressure of 36psi. Dimensions: 3 x 2 x 6 in Important Info: All ceramic discs, tubes, or surfaces MUST soaked in water for at least 30 minutes before use.