Original Z-Shock Technology™ Only one line of shock devices in the world has patented Z-Shock Technology™. Thinking Z means exceptional vertical shock deflection and comfort. But Z innovation goes further. Through active tibial progression, energy is absorbed and redirected, helping an amputee walk or run smoothly and confidently at any speed. Add to this a 100% carbon-fiber shock design of the Renegade prosthetic foot and the result is a durable, maintenance-free device that’s 1/3 the weight of traditional shock feet. As a result, amputees are able to walk farther and faster, expending less energy.