Description: 【Fine Workmanship】The U Shape tube is integrated with the main body, which can get rid of the trouble of bending the trachea, and the trachea connection is beautiful. 【Features】Low pushing pressure, high efficiency, using finer and more stable materials, so that the passing CO2 bubbles are more evenly. With bubble recording function. 【Durable Material】The main body is made of high quality acrylic material, the highly transparent acrylic material are very clear, increases the viewing experience. 【3 Sizes Avaiable】S suitable for aquarium leass than 45cm; M suitable for aquarium approx. 60-90cm; L suitable for aquarium approx. 60-150cm. 【Wide Application】Simple design will better matching with any big or small aquarium fish tanks. Please choose the approiate size for your fish tanks. Specification: Color: transparent Material: acrylic Size Chart: S: 8.5cm x 1.3cm/3.35inch x 0.51inch M: 8.2cmx 1.7cm/3.23inch x 0.67inch L:  8.2cm x 2.4cm/3.23inch x 0.94inch Package Includes: 1 Mini CO2 Diffuser 1 Sunction Cup Note: Please allow slightly errors due to manual measurement and different monitors.