clamp ends duckbill check valve Size: DN50 – DN1800 Connection:c clamp ends Product Feature: There are flowing properties for this duckbill valve. Open and close automatically according to water pressure difference safety without noise and no need of human operation and maintenance. Small flow-in pressure and flow regulates naturally as water pressure. Good seal for reverse non-return and no leakage to avoid flow backwards. The better effect with larger pressure. Anti-corrosion, anti-aging and longer working service. Wide size scope and nominal diameter of DN50 – DN1800.