Abstract: A simplified external bone fixator assembly is provided which allows the surgeon to snap a bone fixation rod into the assembly at any location along the length of the rod. The invention does not require “threading” of the assembly onto the rod starting at the end and sliding it down the length of the rod to the desired location. In particular, a bone pin locking assembly is provided for use with standard bone fixation rods and bone pins. The assembly includes a bone pin vise, a single-piece fixation rod attachment member and a coupling to allow relative adjustment of pin vise and rod attachment member. The single-piece rod attachment member has two opposing jaws that loosely capture the bone fixation rod when the surgeon presses the rod into the attachment member. The assembly may be rigidly fixed to the rod using a bolt which tightens the attachment member onto the rod.