It mean's thatcham cat 2...basically an electronic immobiliser tested by thatcham.just remember it's only cat2 if you have the certificate as should you ever need to claim (even for accident damage so my insureres tell me) before they pay any money they want the certificate. I looked at many car's stating thatcham alarm/immobiliser etc but without the certificate it's just an alarm/immobiliser (no good for insurance) and would need recertifiying by an approved installer (and that is if it has being fitted correctly as some I have seen over the year's have being fitted not to thatcham standard's)
