uxcell 9.4" Long Cylindrical Shape Bubble Release Airstone Aquarium Decoration Tool Color: Black,Gray; Product Name: Air Stone; Net Weight: 390g Total Size: 240mm/ 9.4"; Material: Mineral, Plastic, Metal Stone Size: 195 x 40mm / 7.7" x 1.6" (L*D); Air Tube Port Outer Dia: 5mm / 0.2" An important tool to successfully keep aquatic fish for respiration process. Creates bubbles in fish tank while attached to an air pump(air pump is not included) Please soak the air stone in water for at least 15 minutes before use.