7" DuraVent DuraBlack Trim Collar 7DBK-TC This trim collar is used as a decorative addition for DuraBlack connection to chimney to ensure a solid fit and an aesthetic appearance. 24-gauge strength Lock seams 18" clearance to combustibles Painted black Single-wall interior stove pipe for connecting wood stoves to manufactured chimney Economical and drip-free connection No need for cutting or crimping