This is a hydroponic air stone which is made of silicon carbide. It is a practical and durable domestic product to help fish farming conviniently. Increase oxygen levels, lower CO2 and raise pH. It is an important instrument to successfully keep aquatic fish for process. Durable, washable and sintered by high temperature makes it different from other air stones. It will creates bubbles in fish tank while attached to an air pump.<br> Feature<br> - Color: Grey<br> - Material: Silicon carbide<br> - Size: About 4x4x1.5cm<br> - Practical and durable domestic product.<br> - Increase oxygen levels, lower CO2 and raise pH.<br> - It is an important instrument to successfully keep aquatic fish for process<br> - Durable, washable and sintered by high temperature, different from other air stones<br> - Creates water currents and dazzling underwater scenes<br> - Easy and convenient to use.<br> - Perfect accessories for better life<br> Package list: 4 x air stone