Majestic 6" Chimney Stove Vent BrushChimney Sweep Round Poly BrushesEspecially designed for insulated metal chimneys, stainless steel or metal stove pipes where manufacturers recommend not scratching the flue. These sturdy plastic brushes have 6" of fill and are acid resistant. Fittings are 1/4" threading.Note: Measure the chimney carefully before selecting brush. An oversize brush will not improve cleaning action and could become lodged in the chimney. An undersize brush will not provide the pressure on the walls for proper cleaning.