JW Fusion's Check Valve is a duck bill styled valve that helps prevent backflow. This accessory is a useful tool when running Anchor Bubblers, ActivAir Ornaments, Anchorstone Sand Airstones, and Aircore Sand Airstones to prevent water from back flowing into the Fusion Air Pump.

• Prevents air pump from back-siphoning
• Useful when running Anchor Bubbles, ActivAir Ornaments & Airstones
• Helps prevent blockage & potential air pump damage

*Please DO NOT use it for CO2 system