Features: Compact size, easy to install and remove.High transparent glass material, looks crystal clear, nice and beautiful.Improve the growth and for health of your plants with a sufficient CO2 supply.U shape designed, solved tops of the aquarium tubes' inconvenient.With check for valve, convenient and practical. Suitable for small fish tanks, water plants tanks.Specifications: Material: GlassColor: Red/Black/WhiteSize (Approx.): Check Valve-Caliber 4mm/0.16in, Length 5.5cm/2.17inWeight: Approx.45gPackage Includes: 1 x Glass CO2 Diffuser for Aquarium (Red/Black/White)1 x Check for Valve1 x Suction Cup1 x U-shaped Glass Tubenote: 1.Please allow 0-1cm 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!