5". Product Dimensions: 14 3/4" W x 36" H x 14 3/4" D. 2" clearance to combustibles. 36" square ceiling support box with 5" diameter. There's no need for locking bands or mechanical fasteners. For an extra margin of safety, the inner wall is 25% thicker than competing chimneys. Designed for normal continuous operation at flue gas temperatures of 1000 degrees Fahrenheit. For use with wood stoves, fireplaces, furnaces, boilers, ranges, water heaters, and other wood, coal, or gas-fueled appliances. A vent pipe with a 5" inner diameter is required for this unit.

Size: 5 Inch Product Dimensions: 14 3/4" W x 36" H x 14 3/4" D 2" clearance to combustibles 36" square ceiling support box with 5" diameter No locking bands or mechanical fasteners required Inner wall is 25% thicker than competitive chimneys for an extra margin of safety Designed for normal continuous operation at 1000 degree Fahrenheit flue gas temperatures For use with wood stoves fireplaces furnaces boilers ranges water heaters or other appliances fueled by wood oil coal or gas