Lower arm bar is an undercarriage reinforcement part, which helps to get the best performance that suspensions can naturally offer. It bridges left and right suspension arm’s mounting points together so as to prevent suspension member from twisting, thus wheel alignment keeps straight. It also increases body stiffness because it is mounted at the frame part where it is directory attached to the body. As Lower Arm Bars are installed at the lower part of vehicles body, no worries necessary about C.G, elevations by weight increase. The Ovalshaft, which has a highly strong endurance against the twist,is adopted to the carrying stopper of all items. The section of the shaft and the bracket has made the one constitution by means of welding. the light weight and high strength of the section has been realized.