The F-Series Double-Flapgate Airlock Valves are designed for low-pressure basic dust collection applications with maximum 30″ WC pressure differentials, where low cost is critical and a rotary airlock or slide gate is unnecessary. Operating temperatures for the F-Series are normally in the 250°F range. Used under cyclones, baghouses and collection hoppers, these double flap valves are a low-maintenance and dependable alternative. Just tell us whether you want yours with gravity/counterweight or air-operated actuation.