I bought this to seal up some of the gaps in my cheap vertical smoker.  The metal has warped between the firebox and the cooking chamber and flame and smoke was escaping making temp control difficult.  I laid a bead of this stuff in there and it sealed up just fine.  I have used it to install door gasket in the past but it gets crumbly and came out.  I like silicone much better for that purpose.  I like this for seating firebricks, filling gaps, etc.