Features:1. Made from high quality copper and hose material, which is study and durable. 2. Round air bubble ring, ideal to increase oxygen content into the water. 3. Copper air inlet nozzle, convenient to connect air tube, simple to operate. 4. Not easy to move when placed it under the fish tank bottom. 5. It needs to be matched with a 20w above oxygen pump to use. Specification:Condition:Brand NewMain Material: Copper and hoseColor: As Pictures ShownSize Type: Single Ring Dia 15cm, Single Ring Dia 25cm(optional)Ring Dia: 15cm/5.9in, Ring Dia: 25cm/9.8inRound pipe diameter: 16mm/0.6in(suitable for connect inner dia 8mm/0.3in air tube). Package list: 1 * Air Bubble Ring.Note:Please note that the new type and old type of this product will be sent randomly, and make sure you will not mind before ordering.