Protect basements or low areas from street sewer waste using the PVC 6 in. Backwater Valve Flapper, along with a valve to prevent backflow. The quick action flapper allows unrestricted uni-directional flow and is easy to install. Elastomeric gasket in the flapper ensures a watertight seal. Flapper can be easily removed and replaced if required. This cost efficient valve flapper fits 6 in. backwater valves. Durable backwater valve flapper is made of PVC plastic.