http://www.americainwwii.com/articles/cobra-king-today/
The Sherman tank is the actual "Cobra King" the first tank of the 4th Armored Division to break the siege at Bastogne where the 101st Airborne Division was surrounded. The tank disappeared in World War II then suddenly reappeared in Germany fairly recently. The whole amazing story is in the link above. Looking forward to visiting the museum.
Cobra King is the M4A3E2, nicknamed a "Jumbo" tank. Armor protection was increased in places and was intended to be used attacking the Siegfried line. Only 254 were built. With that extra armor the Jumbo was a natural for a point tank. The tracks have the optional "extended end connectors" installed, which was necessary on the Jumbo because of the extra weight.