Easy and quick assembling and operation. CO2 solenoid controller can ensure accurate CO2 dosing. Solenoid controller can control CO2 output time, avoid waste of CO2. Disposable CO2 cartridge. Easy to set up. Convenient two-way use hanger can be hanged on the tank or placed aside. 3 in 1 Vertical CO2 Diffuser provides goodCO2 dissolving. Easy to change ceramic replacement. Air pipe holder included prevents air pipe from being bended or clogged. All Angle View CO2 Indicator provides accurate reading of CO2 contained. Reusable color chart sticker is included.