Rubber Flapper Swing Check Valves feature a unique, simple design with only one moving part. The flapper does not swing from a hinge pin; it simply flexes open. The seat is on a 45° angle. The flapper travels 35° from open to closed, usually before column reversal can occur. It has non-slam characteristics. The valve requires no regular maintenance. Recommended for water, sewage, gas, oil and rubber lined for chemicals.