3" X 36" B-Vent Gas Singlewall Connector, Singlewall Flexible Construction, Includes An Integral Appliance Draft Hood Connector For Fast Installation, Locks Onto Hart & Cooley Type-B Gas Vent, Requires 1" Clearance To Combustibles Per Installation Instructions, Ul Listed For Use As A Connection From An Appliance To Type-B Gas Vent In Conditioned Spaces Only, Do Not Enclose, Available In 3" Through 5" Diameter And 1' Through 5' Lenghts, Dims:3" X 3" Diameter X 36"L, 1Lb, In Mfg Box, Made In Mexico.