SELKIRK CORP 105036 Gas Chimney Pipe, 5" x 3', Multicolor Easy to assemble and can be combined to obtain the required installation height Couplers overlap 1-1/2" When joined Assembled length is 1-1/2" Less than listed lengths 5" x 3', Gas Vent, Chimney Pipe, Type B Easy to assemble and can be combined to obtain the required installation height Designed for use on approved gas appliances in residential and light commercial and industrial applications Outer material is 28 GA galvanized steel Inner liner is constructed from aluminum