This paper describes an improved design of an external fixator. The new fixator comprises 13 parts which are assembled together. The proposed device materials consist of polyether ether-ketone (PEEK) and stainless steel 316L. The design was subjected to finite-element analysis, and a working model was manufactured and subjected to cyclic mechanical testing. The finite-element analysis showed that the maximum stress was 242.9 MPa and this was less than the yield strength and the fatigue endurance limits for the selected materials. Mechanical testing showed that testing reached run-out of 170,000 cycles with no cracks or damage visible in the device parts.