Tetratec Air Pumps are extremely quiet and powerful, they can be used for increasing oxygen levels, running air-driven ornaments, and operating undergravel filters. They are designed in conjunction with leading sound engineers for maximum noise reduction. They produce high flow rates of air, even in deeper aquariums and have adjustable airflow. They have a modern design with state-of-the-art technology and have a 3 year manufacturers guarantee. CE certified, TUV/GS tested - safety and reliability assured. Suitable for Aquariums 10L - 60L. Maximum pumping Rate 50l/h. Power consumption 2.0Watt. Installation... Place the air pump outside the aquarium, away from areas where it may get splashed. Attach a length of standard airline to the outlet, and run this into the aquarium. Attach the airline to a TetraTec AS air stone, or to an air-powered ornament. It is important to install a TetraTec CV4 check-valve in the airline to prevent water being drawn into the pump. Use the flow-control valve that comes with each APS pump to control the amount of air produced. Always read the instructions carefully before use.