Co2 Bubble Counter & Diffuser With Check Valve, Single/dual For Aquarium Air. ZRDR CO2 Bubble Counter for Aquariums Enhance Your Aquarium with the ZRDR CO2 Bubble Counter, Expertly Designed from Premium Aluminum Alloy and Acrylic for Long-lasting Durability. This Essential Tool Allows You to Accurately Monitor and Manage CO2 Levels in Your Tank, Promoting Vibrant Plant Growth and a Healthy Aquatic Environment. Equipped with a Non-return Function, the Bubble Counter Effectively Prevents Backflow During Pressure Changes, Ensuring the Protection of Your Water Plants and CO2 Tanks from Potential Harm. Its Easy Installation and User-friendly Design Make It an Ideal Choice for Hobbyists and Professionals Alike. Choose Between Single-head and Dual-head Options to Perfectly Suit Your Specific Requirements. Features: - High-Quality Material: Constructed from Durable Aluminum Alloy and Acrylic. - Non-Return Function: Protects Your Setup by Preventing Backflow During Pressure Changes. - Precise CO2 Monitoring: Accurately Regulates CO2 Levels for Optimal Plant Health. - Easy Installation: Simplified Setup for Both Single and Dual-head Configurations. - Versatile Options: Available in Single-head and Dual-head Models. - Material: Aluminum Alloy & Acrylic - Type: Single Head (8 X 2 Cm), Double Head (8.2 X 2 Cm) - Weight: Approx. 32–34g Transform Your Aquarium with the ZRDR CO2 Bubble Counter for Vibrant Plant Life and Enhanced Visual Appeal..