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 monitor 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 Specification: Material: PC Size Chart: Suitable for water pipe with inner diameter: 12mm/0.47inch or Suitable for water pipe with inner diameter: 16mm/0.63inch (optional) Package Includes: 1 Aquarium CO2 External Atomizer set Note: Please allow slightly errors 1-2cm/0.39-0.79inch differences due to manual measurement.