Description: Aquarium lily tube, inlet and outlet set, water for surface skimming filter. Inflow and outflow filter tubes are designed to create the ideal flow of water for plant growth. Effectively remove oil stains on the for surface of fish tank and fish tank, and provide a fresh and healthy breathing environment. The inflow flow at the bottom is adjustable, and the water level of the oil absorption film can be controlled, which is convenient for filtering and isolating impurity water and preventing fish and shrimp from inhaling. Made of glass, simple and beautiful. Comes with suction cup for easy installation on your aquarium. With for surface oil film function, easy to clean. Specification: Material: Glass Color: Clear Size: Approx. 13mm/0.51 inch Fits 1/2'' ID tubing (12mm/0.47 inch inner/16mm/0.63 inch outer) 17mm/0.67 inch For with 5/8'' ID (16mm/0.63 inch inside/22mm/0.87 inch outside) Package Includes: 1 Set Aquarium for Surface Skimmer Note: 1. Please allow slightly error due to manual measurement. 2. Due to the difference between different monitors, the picture may not reflect the actual color of the item. 3. Wish you a wonderful online shopping! Customer satisfaction is our primary concern. If the product is somehow cracked or broken during shipping, please feel free to contact us. We will try our best to give you a satisfactory solution.