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Small and Compact Fits standard aquarium air-line 4mm inner diameter Allows air to travel in one direction only. Stops water coming back down the air tube Easy to install - just cut the airline between the air stone and the air pump and insert check valve into air line
Small and Compact Fits standard aquarium air-line 4mm inner diameter Allows air to travel in one direction only. Stops water coming back down the air tube Easy to install - just cut the airline between the air stone and the air pump and insert check valve into air line