The grippers for industrial robots with two or more DOF and a single driving motor are used to grasp the work pieces with poor stiffness in terms of low positioning accuracy. These grippers have a simple structure and are proper and suitable to blanks or semi-finished work pieces, with major dimensional deviations, which are handled between various tasks from manufacturing process. The geometrical symmetry of the system made by fingers and work piece is got by a suitable distribution of the force. This distribution is realized by an adequate design of the gripper fingers. In present paper, some considerations concerning the optimum synthesis if the gripper mechanism with two multi-links fingers are shown.