About this item 【High Quality Materials】Our aquarium check valve is made of high-quality PVC material, strong and durable, easy to use, built in accordance with strict quality control standards, and improved design to improve durability. 【Indispensable Accessories Of The Air Pump】Prevent the water in the fish tank from ing back into the air pump, burn the air pump to avoid danger. 【High Quality Materials】Our aquarium check valve is made of high-quality PVC material, strong and durable, easy to use, built in accordance with strict quality control standards, and improved design to improve durability.aquarium air pump accessories 【Exquisite Workmanship】Our aquarium check valve adopts high specification technology, the perfect combination of economy and high quality. Reliable use, long service life, not easy to damage, and can be used for a long time. 【High Fault Tolerance】When the position of the air pump is lower than the surface of the water, to prevent water back damage to the front end of the air pump or other product equipment, after the addition of stop valve air pump can be higher than the surface of the water or lower than the surface of the water placed.