Canon Speedlight 133D - CAT System for FTb, FTbn, EF and F-1

[Lloydy]

A Canon Speedlight 133D with the attachment that clips to the bayonets found on the outside of suitable Canon lenses. I have never seen this before and can't find much information about it. I
The Speedlight has had leaking batteries but I have thoroughly cleaned the terminals.

Information from DigiChromeEd.
When the Canon FD lens mount was introduced with the FTb and F-1 cameras, a special Canon electronic flash system was introduced as well. Canon called this the CAT (Canon Auto Tuning) system. There were two models, the Speedlite 133D and the Speedlite 500A. The Speedlite 133D worked on the FTb, FTbn, EF and F-1. A Flash Auto Ring was fitted onto the front bayonet mount of the lens with the two prongs on the back catching the stud on the lens focusing ring, so that the prongs were moved as the lens was focused. A cable from the Flash Auto Ring was then plugged into the flash. Once this had been done and the camera metering switch placed in the flash position, the camera's light meter needle could be lined up with the circle by turning the aperture ring after focusing, and flash exposure was automatic.

More information here -
http://www.mir.com.my/rb/photography/hardwares/classics/canonf1/html/cat/index.htm

http://www.mir.com.my/rb/photography/hardwares/classics/canonf1/html/cat/operate2.htm









This is untested but is visually in very good condition.

I have no idea what it is worth so it's open to offers.