Cusco Power Brace Rear End Subaru WRX STI 2015+ Cusco Chassis Bar Power Brace Rear (Steel) Bracing for Subaru WRX Cusco Rear Member Side Power Brace 2015 2021 Subaru WRX STI 2014 Cusco Rear Lower Power Brace For 02 07 Subaru Impreza WRX 04 07 STI Cusco Lower Cross Member Bar Power Brace Front (Steel) Bracing for. Developed by chassis engineers based off the data logged directly from CUSCO motorsports research. The power brace strengthens chassis and minimizes body flex especially at cornering loads, enabling optimal suspension movement at the intended geometrically aligned state. Having the same effect as stitch welding a chassis, the Power Brace series are Bolt on design with some minor body piece (under cover interior etc) trimming and completely effective on all vehicle chassis no matter stock or highly modified. These bars are made and constructed by lightweight steel and engineered inside & out by using the state of the art chassis stress test simulation software by leading motorsports professionals.