In the late 1960s, the U.S.A. was working to create a well-protected tank destroyer with high-powered weapons to fight prospective enemy tanks. A high-powered 155 mm or 165 mm gun was considered for the armament, while a radar rangefinder and a secondary optical rangefinder were planned for increased accuracy. The vehicle's hull and turret were supposed to have welded cage armor for better protection against HEAT shells. As a result, the prospective project turned out too complicated and expensive, and so it was abandoned.