Use Selkirk"s trim collar for a 6" roof support to conceal the gap between the chimney pipe and the ceiling cut-out.Fabricated from 22-gauge cold roll steel. Up to 60% thicker than most hardware store brandsLaser and Advanced Resistance-welded seams makes snap together pipe obsolete. Guarantees a completely sealed seam: no smoke or flue leakageSaf-T Pipe offers a Full range of parts and sizes Beaded for furnace cementBlack high-temperature, low-luster finish painted with the highest quality silicone based stove paintIndividually wrapped and packaged. Readily available at Hearth Products specialty shops and from professional installers