Minuteman International Smoke Pipe Damper: Material: Cast iron Product Type: Venting kit Material: Iron Dimensions Size 7'' Diameter Overall Depth - Front to Back: 7'' Size 6'' Diameter Overall Width - Side to Side: 6'' Overall Depth - Front to Back: 6'' Size 5'' Diameter Overall Width - Side to Side: 5'' Overall Depth - Front to Back: 5'' Size 4'' Diameter Overall Width - Side to Side: 4'' Size 3'' Diameter Overall Width - Side to Side: 3'' Overall Depth - Front to Back: 3''