Tinker's arms

The first tinker's arm was created by the Tinker's Guild in Ratchet for Samuel Wrenchwright, a popular member who lost a limb in an accident. When others saw that Wrenchwright had not only gained a useful limb but also increased strength, they asked the tinkers to develop a version that might be used without the loss of a living arm. The resulting apparatus is strapped to the wearer's arms.