This is one of the few M4 Composites around. It is in the General Patton Memorial Museum located at Chiriaco Summit, California.
The tank was a range recovery. I am informed that it was produced early in the production run. As such it is your typical M4 composite as seen in use by British and Amercan units.
The cast in armor reinforcement is fairly obvious in picture 32. The commander's hatch and the lack of the pistol port are also of note.

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