Pawfly 6 Pcs Aquarium Check Valves For Common Air Pumps Red Plastic One-Way Non-Return Valves Pump Protectors For Standard 3/16 Inch Airline Tubing Fish Tank Accessories For Aeration Setup

The check valves are for common aquarium air pumps. Please DO NOT use them with CO2 system. Great one way check valve for aquarium and fish tank. Protect you air pump by preventing aquarium water from back siphoning during a power outage. Made of durable clear plastic. Net weight: 0.14 oz / 4 g. Please use a paperclip to poke it from Input side to Output side when the outlet inside gets stuck. Air Hole Diameter: 0.15 / 4mm; Overall Size: 2.1 x 0.58 / 5.3 x 1.5 cm (LMax.D) Package Content: 6 Pcs x Air Check Valve