The PVC DWV closet flange features a female NPT thread connection. The closet flange is secured to the floor of the dwelling so that a toilet can be affixed to it and allow for a pipe connection (under the floor) to continue the piping for evacuation of the used water. Please refer to NIBCO technical data sheets and catalogs for engineering and installation information. Polyvinyl chloride (PVC) is the most frequently specified of all thermoplastic materials because of its light weight, durability, and cost-effectiveness. PVC DWV is easy to install and is joined by solvent cementing or threading.