The purpose of this study was to determine the effect of wire diameter, lumen size, and length of coil spring on the load produced as a function of displacement of SS and NITI coil springs. This study was based on 60 samples of open and closed coil springs. Open coil springs were tested in compression and closed coil spring in tension. The load values produced by coil spring as function of displacement were measured twice both during activation (loading) and deactivation (unloading). It was seen that effect of lumen size has less effect than the diameter of the wire on load produced and maximum load attained of open and closed coil spring. The length of the spring had the least effect.