Use for concentric horizontal terminations. Includes 2 appliance adapters, white wall plate, white firestop, and co-linear adapter. White Termination with Bird Guard Screen. UV resistant. Inner plate is 8 5/8” (220mm) square, outer plate is 9 7/16” (240mm) square for all flue sizes. Includes 2 Locking Clamps and two Adapter Connector clamps. Adapters included to transition from PVC appliance outlet to twin pipe PolyPro. PolyPro is a polypropylene vent pipe for use with ANSI Category II and IV gas-burning appliances, including high efficiency water heaters, condensing boilers and warm air furnaces.