Check the listing for details. Air Stone Copper Bubble Stones Aerator Air Pumps Accessories Oxygen Diffuser. Condition: New, Made in China. Listed at 7.68 USD. Features: brand new and high quality Increase oxygen levels,easy and convenient to use. It is an important instrument to keep aquatic fish for respiration process. Creates bubbles in fish for tank while attached to an air pump. Creates water currents and dazzling underwater scenes. Specifications: Material: Mineral stone + Copper Size: One Size Size: length 4cm(1.57in) Suitable for inner diameter 4mm soft tube Color: As pictures show Package Includes: 1Pc xBubble Stone(No retail package) note: 1.Please allow 1-3cm error due to manual measurement. pls make sure you do not mind before you bid. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you!