CO2 Bubble Counter Single/Double Head

Aquarium CO2 Bubble Counter Single/Double Head   PREMIUM QUALITY - This CO2 Bubble Counter is made of high quality material, which is durable and reliable. NON-RETURN FUNCTION - With non-return function, this CO2 Regulator can prevent the backflow when the pressure changes. It prevents damage to your CO2 system. ESSENTIAL - Clear and precise bubble formation allows you to count bubbles with ease. CONVENIENT INSTALLTION -This Bubble Counter comes with a built-in check valve and attaches to the regulator for an easy set-up. Simply screw on, and you're done! MEET YOUR NEEDS - Double head and single head options available.