Metal-Fab's round and oval Type-B vent is listed by Underwriters Laboratories for use with approved category 1 gas furnaces, heaters, and boilers. A category 1 appliance operates with a non-positive vent static pressure. The double wall design of B-vent enables the product to be used in homes and commercial buildings at close clearance to combustible. Metal-Fab's B-vent design incorporates features that make installation quick, easy, and safe.
Adjustable Round Gas Vent Pipe, Type B Double Wall, Series: M, 4 in ID Dia, 12 in Length, 1/4 in Thickness, Aluminum, Domestic