GenShock is an energy-harvesting, semi-active shock absorber. The device converts vertical travel of a vehicle suspension system to useful electricity. On defense platforms, this power ranges from a few hundred watts to several kilowatts. Conventional shock absorbers provide damping by dissipating suspension energy as heat, while GenShock provides damping by generating electricity. For an internal combustion engine (ICE) vehicle, the energy harvested by GenShock is used for reducing alternator load. The energy can also be conditioned for battery charging to address vehicle hotel loads. GenShock is also semi-active capable, in which each unit can stiffen or loosen in concert with the terrain, vehicle speed and load conditions for improved maneuverability. This paper presents a characterization of GenShock technology in its form and function of a direct replacement shock absorber that has regenerative and semi-active capabilities.