Outer skin is made from 304 grade stainless steel and is 0.4mm thick. This is then powder coated in a high temperature Black finish. The Inner skin is made from 316 grade stainless steel and is 0.4mm thick. Insulation is compressed rockwool giving a density of 128kg/m3. All parts are fully welded.
Distance to combustibles is 50mm.
TWPro Twin Wall Insulated Chimney parts are secured together by using a Locking Band (supplied).
Make sure that you keep a distance of 50mm from the outside of the flue to any combustible material (wood, plaster board).