Item Type: Kitchen Range Hoods Check Valve Material: ABS, stainless steel, silicone Suitable for Pipe Diameter: Approx. 150-180mm / 5.9-7.1in Package List 1 x Kitchen Range Hoods Check Valve 2 x Cable Tie 1 x Steel Stick 1Eliminate Odors: You only need to open the check valve, and automatically open the exhaust valve to exhaust smoke through the exhaust air. 2One Way Check Valve: Since this check valve is one way, it can firmly block outdoor odors and mosquitoes after it is closed, and the fumes will not flow back. 3Quick Sealing: The check valve can be quickly sealed after exhausting the smoke, the silicone sealing ring can make it fit tightly without leaving gaps. 4Fine Workmanship: The check valve is made of ABS material as a whole, with built in stainless steel strong spring, with excellent performance. 5Easy Installation: The non return valve is designed to upgrade the level, and the main body and the fixed seat can be disassembled to make the installation faster.