Lunar Roving Vehicle

The "Qualification Test Unit," was a very close replica of the units that flew. Using special test chambers, engineers purposely subjected the qualification unit to conditions many times as severe as those expected on an actual mission. When the tests were finished, given the stresses it had been subject to, the qualification unit could not safely be used in space.

Lunar Roving Vehicle
Qualification Test Unit
National Air and Space Museum, Washington D.C.