Lock Ring
UL 441
12 Inch
400 Deg F
4 Inch I.D. x 4.5 Inch O.D.
Aluminum (Inner Wall), G90 Galvanized Steel (Outer Wall)
0.012 Inch (Inner Wall), 0.018 Inch (Outer Wall)
Installation Instructions are Supplied with Cap and Support
Type B Gas Vent, Double Wall, Round