Product Specification: Item type: Glass Dissolver Color: Transparent Material: Glass Package Includes: 1 x glass oxygen bubbler 2 x suction cups 1 x air stone 1 x oxygen tube 1X black check valve Product Features: Made of high quality and beautiful glass. Glass cup design to prevent the bubble from sputtering out of the tank or splash onto the lamp or cylinder. Suitable for all kinds freshwater fish, shrimp tanks, planted tank, etc. Non-Return Check Valve: The check valves are made of clear plastic and protect your air pump by preventing aquarium water from back siphoning during a power outage. Sweet Tips: 1.Please allow a little size error due to hand measure. 2.Color may be a little different due to monitor and light brightness from pictures. Thank you for your understands.