Kev,i think what you have is a Sterling Excel Thatcham Cat 2 Immobilisor as i have fitted to my "Nearly Supersport", i think that's possibly what Omex recommended for the Supersport set up. Check on your torpedo, does it say "Stirling"...handy to know! if you should have an issue, however touch wood...its possibly a better bit of kit than mentioned above. anyway dont tell the world but its (not) easliy unscrewed and overriden in a remote part of the car, a location of which if i were to tell you i would have to immediatly shoot you.