Hygger CO2 Generator Kit w/motorized valveWhy Youll Love It Select a professional grade CO generator for safe operation for aquatic plant growth. The hygger HC031 CO2 generator system features a state of the art motor valve, which allows you to set precise timers and ensures consistent CO2 injection at your desired intervals. Key Features Revolutionary Motor Valve & Timer Its time to upgrade your aquarium setup with the HC031 advanced CO2 generator system. You can set precise timers to ensure