JSP8E4 06820 Double wall black stove pipe8* 45 degree elbow By GSW GSW SuperChimney Twenty-One A big company which makes a lot of chimney, so 6" and 8" are immediately available. Good products, competitive pricing. Their Chimney Twenty-One has a wall thickness of 1". Their Chimney 2100 (primarily for the Canadian market) has a wall thickness of 2".