Pawfly 4 PCS Air Stone Bar 4 Inch Bubble Release Mineral Blue Airstones for Fish Tank Aquarium Pump
- Specially designed non-return valves will protect your air pump by preventing aquarium water from back siphoning during a power outage.
- They are made of plastic material for long time use.
- Place these air pump check valves in your airline tubing between your air pump and aquarium water to prevent water returning down the air line.
- Fits standard aquarium airline tubing with inner diameter about 4mm.