The rationale for some handle characteristics is not clear. Recently, however, handle characteristic have received some attention. In the 1950s, Damon and other at western electric in Kansas city developed bent handles for needle-nose pliers used in electronics assembly. In the 1970s, without knowledge of previous work, Bennett patented handles for tools and sporting goods. His patent has a bend of 19+-5 and a particular aspect ratio for the handle cross section. He noted that when one curls the fingers to grasp something, the opening formed by the fingers is not round, but is oval. He also noted that when one grip some tools, the user’s wrist bends to is limit he chose to bend the handle instead. Examples of Bennett’s designs are shown in Figure 13-19(b,c)