Abstract: An anti-theft device mountable around a steering post column of an automotive vehicle so to enclose the vehicle ignition lock and prevent insertion of a key thereinto by an unauthorized person; the device consisting of strong metal case having an opening on one side into which the ignition lock protrudes from the steering post column, the case being secured to the column by means of a U-shaped rod that fits around the column and into openings in the case wherein toothed notches along the rod are engaged by a sliding plate rigidly prevented from sliding by being stationarily locked with a padlock.