Theft prevention device for automobiles

A theft prevention device for vehicles having steering wheels comprises a tubular metal head portion (100) having a longitudinal slot (8) adapted to fit over part of the annulus of a steering wheel (2). The head portion is connected to a handle (11) which includes a rotatable shaft (10), rotatably connected to a part cylindrical rotatable steering wheel locking sleeve assembly (4) having a locking protrusion (41) which can be selectively rotated behind the annulus of the steering wheel and locked in place by means of a lock (2) at the end of the head portion (100) remote from the handle (11). This makes it easy to fit the device to a steering wheel and to unlock it therefrom whilst at the same time retaining the advantages of prior art devices preventing complete rotation of the steering wheel with the device attached.