Imperial's black trim collars should be installed where the flue pipe connects to the masonry chimney breech. It will provide a finished appearance. Install on wall where flue pipe connects to masonry chimney breechProvides a finished appearanceThe 8" round black matte trim collar is installed on wall or ceiling around the stove pipe where it connects to the chimney.Imperial's black trim collars should be installed where the flue pipe connects to the masonry chimney breech. It will provide a finished appearance.