The Chihiros CO2 Spiral bubble Counter is a high-quality and stylish accessory for the precise addition of CO2 to aquariums. With its elegant, spiral design, it enables precise monitoring of the CO2 supply and ensures an even supply to your aquatic plants.Chihiros CO2 Spiral Bubble Counter+ Made of borosilicate glass material, high clearness+ Compatible with pressurized CO2 tanks and DIY yeast bottles+ Rhinox shape glass bubble counter that helps you to estimate amount of CO2 release into your aquarium+ Bubbles moves along the spiral upward, and when it escape from the spiral, you can count bubbles per second+ Material: Clear Borosilicate Glass+ Size: 135 x 20mm+ comes complete with suction cups