The Rain Harvesting 90mm overflow flap valve helps keep mosquitoes, frogs and other pests out of tank overflow pipework. The flap opens as water flows out and closes when the flow stops, while its screened vent allows air to pass.
The 90mm male spigot fits into a matching female socket at a tank overflow outlet or horizontal overflow connection. Install with the hinge at the top so the flap can return to its closed position.
The screen can be hosed or brushed clean if debris builds up. Leave access to the flap and keep it free to move.
Rain Harvesting Vented Flap Valve Installation & Specifications