Pipe sections combine corrosion-resistant stainless steel and sturdy galvanized steel for strong chimney construction Lightweight pipe with snap-lock joints offers faster easier installations Features a space-age refractory blanket between the stainles s steel/galvanized walls to withstand intermittent temperatures up to 2100 degrees F as called for in UL 103 HT Standard Requires 2 air space to combustibles. 6 ID - 9 OD Lgth In=12