Feature:1. No Backflow Design: Featuring disc type non return design, this check valve ensures oil fume enter but do not exit, and the gravity spring tightly closes to prevent oil fumes from flowing back2. Level Bubble: Equipped with a level bubble for accurate horizontal installation, ensuring superior sealing and eliminating installation deviations, providing convenience and improving efficiency3. ABS Material: This check valve is made of thickened ABS material, which is aging and high temperature resisting, offering enhanced security during use with its durability and lasting performance4. Transparent Side: This kitchen check valve features a side transparent window design, providing convenient visual access to the internal status, facilitating easy observation and maintenance5. Large Caliber: This check valve has a large diameter, Suitable for kitchen exhaust system, range hoods duct, ensuring efficient oil fume ventilation while blocking unwanted backward draftsSpecification:Item Type: Oil Fume Check ValveProduct Material: ABS.Package List:1 x Exhaust Duct Valve2 x Accessories