Blast from the Past:
Teledyne Expeditionary Tank
Another contender in the US Army's search for the Airborne Light Tank. At the time airborne equals to C130 cargo aircraft transportability and air dropping.
It was 19tons combat loaded and was two tonnes heavier than the winner of the competition FMC's CCVL. CCVL then evolves into M8 Armored Gun System which was later cancelled by the Army. But M8 is by itself another subject.
By the way, any body recognizes the turret? Hint: M1128...
Styrker Mobile Gun System: