Good finish and works with heater ,no transfer of heat to surrounding areas Use it to run the exhaust through the insulate wall. Fit for Chinese diesel parking heaters , marine exhaust hose, thru hull fitting, 316 stainless steel thru hull skin also used as marine exhaust flapper, generator exhaust extension,boat hull or car hull exhaust port. Thru hull fittings for boats which fit for 24 mm inner diameter hose pipe. Packaging :1 piece thru hull,3 piece screws,3 piece big gasket. Packaging :1 piece thru hull,3 piece screws,3 piece big gasket.