Duravent's DVL double wall black stove pipe allows you to reduce the clearance from a single wall pipe (which is 18") down to 6". This often allows you to install the stove closer to the wall. The double-wall pipe also keeps the flue gases hotter which increases draft and reduces the amount of creosote build-up in the chimney. NOTE: This is a connector pipe designed to be used within a room from the appliance to a chimney. it is not to be used beyond the wall or ceiling it is installed in. See the installation instructions.