Dymax Stainless Steel CO2 diffuser uses special ceramic refinement. The quartz plate has a good ultra fine effect and high dissolution rate that breaks up a steady stream of carbon dioxide into tiny bubbles. These very small bubbles produce a much higher surface area to volume ratio than large ones; making it easier for the gas to be diffused into water. High quality stainless steel; easy installation; excellent diffusion of CO2; and replacement ceramic disc’s available. Diameter of diffuser: 36mm. Total length: 8cm. Length of Spacing 2cm. Replaceable ceramic disc. DM758