uxcell Cylindrical Shaped Fish Bowl Aquarium Air Bubble Creator Mineral Stone 5 Pcs Package Content: 10 x Aquarium Air Stone; Net Weight: 60g; Model: NAJ-041 Color: Blue; Material: Mineral, Plastic; Connector Size: 4.5 x 2.5mm/ 0.18" x 0.1"(Outer Dia*Inner Dia) Made of mineral material, it effectively create water currents and dazzling underwater scenes. Creates bubbles in fish tank while attached to an air pump(Not Included). An ideal tool to add oxygen to your hydroponic growing system.