UNS Pro CO2 Manifold BlockMultiple manifold blocks may be added to the Ultum Nature Systems Pro Dual Stage Regulator. Each additional unit allows for CO2 distribution into multiple planted aquariums. Each manifold block consists of a detachable bubble counter, check valve and precise needle valve. Increase the number of manifold blocks used to create hassle free and simple planted aquarium CO2 injection systems. Specifications: Made with High Quality Aluminum Precision Needle