4 inch Round Air Stone Bubbler BLACK Premium Grade Bubble Diffuser. 90 Degree Metal Inlet Prevents Kinks! 3 Suction Cups to Hold in Place. Perfect for Hydroponics, Aquaponics, Ponds, Aquariums, etc. * RECOMMENDED PREMIUM GRADE BUBBLE DIFFUSER for smart Aquaponics, Aquaculture, Hydroponics, Ponds, and Aquariums. When mediocre just won't do, get this finest bubbler from the experts at Cz Garden. * 4 INCH ROUND AIR STONE measures 6 inches long, 5 inches wide, and 1.5 inches high. Does a fantastic job of adding oxygen to your water for maximum growth and healthy, happy fish. The Micro-Pore Design aerates, circulates, and extends the life of nutrient solution. Promotes healthy roots and exceptional growth. * 3 SUCTION CUPS keep the Air Stone from floating around your tank or pond. The cups hold it firmly and securely in place until you're ready to release and move the stone. Set it and forget it while the bubbler works 24/7 for a perfect water environment. * VERSATILE & CONVENIENT 90 DEGREE METAL AIR INLET. Easily connect either 3/8" ID or 1/4" ID tubing. You don't get kinks like others are plagued with. Your bubbler puts out just the right amount of oxygen without drop offs and drop outs caused by kinking. * 100% MONEY BACK GUARANTEE ensures this will quickly become your favorite no-risk purchase. Many people are stocking up with several of these for their grow operations and fish tanks. HURRY AND BUY NOW while we have this very popular accessory in plentiful supply. This makes a great birthday gift or holiday present.