Uxcell Aquarium Semicircle Shape Bubble Air Stone, 6-Inch, Gray Help to keep fish healthy and adds to the beauty of the aquarium; Made of mineral material It effectively create water currents and dazzling underwater scenes Product Name : Aquarium Air Stone; Stone Size : 153mm/6" (Dia) Connector SizeInput : 5.3 x 3mm/0.2" x 0.1"(Outer Dia*Inner Dia); Total Length : 85mm/3.3" Material : Mineral