Triple-wall designed, the Duravent 6 x 36-inch Galvanized Class A Triple Wall Chimney Pipe features a 10-inch outer diameter insulation layer for safe venting. Insulated by 2 layers—ceramic blanket and air space—the chimney venting pipe is perfect for wood stoves with a 6-inch flue system. The wide flue system allows for better performance and efficiency of stoves while maintaining safe performance.