Feature: 1. 100% brand new and high quality. 2. Increase oxygen levels, lower CO2 and raise PH. 3. It is an important instrument to successfully keep aquatic fish for respiration process. 4. Durable, washable and sintered by high temperature. 5. Creates water currents and dazzling underwater scenes. 6. Creates bubbles in fish tank while attached to an air pump(air pump is not included). 7. 100% brand new and high quality 8. Increase oxygen levels, lower CO2 and raise PH 9. It is an important instrument to successfully keep aquatic fish for respiration process 10. Durable, washable and sintered by high temperature 11. After-Sales Guarantee: Galapara assured after-sales guarantee, 30 days money back guarantee. No matter if you are not satisfied,you can contact us by email.We will provide solution or money back guarantee. Specification: This air bubble stone is a perfect accessory for fish tank. It can create bubbles in fish tank while attached to an air pump(air pump is not included). Features: 100% brand new and high quality. Increase oxygen levels, lower CO2 and raise PH. It is an important instrument to successfully keep aquatic fish for respiration process. , washable and sintered by high temperature. Creates bubbles in fish tank while attached to an air pump(air pump is not included). Creates water currents and dazzling underwater scenes. Specifications: Color: Gray Material: Mineral Stone + Plastic Item Size: Approx. 40mm * 15mm (D * H) Item Weight: Approx. 30g / 1oz Note: This air stone is suitable for using in 30-60cm fish tanks. Suitable for inner diameter 4mm soft tube. Before use, please immerse it in the water for 15 minutes. It it doesn't have bubbles in one part, please change the pump of higher power. It will not work as normal if you attach to the submersible pump. Package List: 1 * Air Stone Package List: 1 * Air Stone