Fitted to the top of central heating or dual fuel towel rails, our automatic air vent will allow any build-up of air to seep out slowly and silently through the valve, enabling the water level to rise and close the mechanism again. This removes the need to bleed radiators manually and keeps radiators fully heat generating and efficient. Browse More From This Collection Manual Valves Modern TRV and Lockshield Sets Ornate TRV and Lockshield Sets Corner Valves Angled Valves Straight Valves Manual Dual Fuel Valves TRV Dual Fuel Valves T-Pieces Air Vent & Plug Sets 18mm Pipe Sleeves Element Shroud Cover Sets Round Valves Square Valves Standard and Digital Elements Traditional Radiators