Unidirectional Check Valve 4 mm Air Oxygen Pump

Product Name: 4mm Unidirectional Check Valves for Aquarium Colour: blue. Size: 4mm Aquarium Pipe Material: Plastic Product Overview This 4mm check valve is an essential accessory for aquarium aeration systems. Designed to allow air circulation in one direction, this 4mm one-way check valve effectively prevents water from flowing back to the air pump. Main function The 4mm check valve acts as a safety barrier for your aquarium equipment. When the pump stops or a power failure occurs, the aquarium 4mm check valve immediately blocks the return of water into the hose and protects the pump from damage.