Description: [Premium Material]:Crafted from quality PC,this Aquarium CO2 external refiner is designed for durability and longevity,ensuring it withstands regular use in your aquarium setup [Space Saving]:The sleek and transparent design not only adds a modern touch to your aquarium but also helps free up internal space,making it an ideal choice for compact setups [Easy Installation and Use]:With its user-friendly design,this Outer Atomizer is simple to install and operate,allowing you to effortlessly integrate it into your existing aquarium system [Bubble Counting Feature]:Equipped with a bubble counting function,this device allows you to CO2 levels accurately,ensuring optimal conditions for your aquatic plants and fishes [Complete Set Included]:The package comes with 1 complete set of the CO2 diffuser system,providing everything you need for immediate setup and use in your aquarium environment Specifications: Material:PC Size: Suitable for water pipe with inner diameter: 12mm/0.47inch or Suitable for water pipe with inner diameter:16mm/0.63inch (optional) Note: Please allow slightly errors 1-2cm/0.39-0.79inch differences due to manual measurement. Package included: 1 Aquarium CO2 External Atomizer set