Hi Darryl,

heli-coils look like coils of wire, the "PermaPlug Spark Plug Thread Repair Kit" is a solid metal insert, i think it would be
stronger.
I never have much luck with Stihl chainsaws, all i did was remove
the spark plug, the thread came out with it! banghead

Oh well I'll fix it then sell it.

cheers2 gmax