SODIAL Aquarium Fish Tank CO2 Diffuser Carbon Dioxide Reactor with Ceramic Disc + 2 Suckers Extra fine ceramic micro bubble diffuser plate CO2 Diffuser Size(L x W ): Approx. 2.36 x 1.18 inch / 6 x 3cm Glass Cup Diameter: Approx. 0.79inch / 2cm Material: Glass and Ceramic disc Color: Clear