Originally Posted by
Jeff Wills
+1. I remember those also. Not a great locking mechanism, since all you needed was an ordinary hex (Allen) wrench to remove the wheel. They'd slow down the opportunistic thief, though.
The original could be opened with a regular hex key. The later versions, had a pin in the middle to keep the key out, and required a drilled out key. Still not super secure, but can't be opened by the casual thief. This was a nice option for wheel protection in urban areas. I think what killed it was the change to aluminum external cam QRs.