3" PelletVent PRO, Wall Thimble/Ceiling Support Cover.
This is a support cover for 3" Wall Thimble, this is from the PelletVent Pro Line. This works for both the 3" and 4" pellet pipe. It has the duralock tightening system, to get a tight fit. Decorative cover for ceiling support boxes and wall thimbles. It is painted black. You need to use a reduction collar.