4" PelletVent Pro Galvalume Tall Cone Roof Flashing 4PVP-FF This tall cone roof flashing is used to weather-proof the penetration of vent pipe through the roof. Storm collar required. Select roof flashing based on pitch of roof. Use on flat roofs chase enclosures or masonry chimney. Use with pellet oil corn and bio-fuel appliances Laser-welded super ferritic stainless steel inner walls and galvalume outer walls Outer diameter is 5/8" larger than inner diameter 1" clearance to combustibles No additional gaskets or sealants needed The precise fit of twist-lock connections is fast secure and leak resistant. Adaptability is provided by swivel elbow connections and multiple termination options Laser-welded double-wall pipe with a .012†inner wall of corrosion resistant stainless steel and a .018†laser-welded galvalume outer wall. Painted black exterior available. Primary metal-to-metal connection seals joint. Encapsulated O-ring provides a secondary seal.