Constant force spring is made by winding the steel strip into a coil which exerts a nearly constant retraining force to resist uncoiling. By comparing the differences between constant force spring and traditional wire springs, the advantages will be obtain as following: To exert nearly constant force during entire extension. Short initial deflection, it means that reaching the rated load at short extension. Long extension capability. The product range from 0.03~0.75mm in thickness and 1~50mm in width.

Power spring is the steel strip wound on an arbor and confined in a spring case. When a force rotates the spring, arbor will have relative motion with spring case and store rotational energy in the form of torque. When the force is removed, torque releases through the central arbor or the spring case in which it is restrained. The product range from 0.03~0.75mm in thickness and 1~50mm in width.