There were approximately 40 serviceable Shermans of CCB, 10th Armored defending Bastogne, with another dozen or so towed to fixed positions and used as armored pill boxes. Adding to this was another 11 Shermans and 14 M10s of CCR, 9th Armored.
To this number of fighting vehicles should be added the light tanks (approximately 12), cavalry assault guns, and antiaircraft artillery automatic weapons carriers. At least nine M8 armored cars were also available, and one actually killed a King Tiger by firing point-blank into its engine compartment.
A very important addition to the Bastogne force was provided by the 705th Tank Destroyer Battalion, which was equipped with M18s and two platoons of M36s.
My regards,
Widewing