Cusco Power Brace Rear End 2015 2021 Subaru WRX STi (VA) Cusco Chassis Braces for CUS6A1 492 RL Fitment Industries Cusco Lower Side Floor Bar Power Braces Rear (Steel) Bracing for Cusco Power Brace, Rear End, 2008 GH WRX STi Suspension Misc Cusco Trunk Bar Plus Power Brace Rear(Steel) Bracing for Subaru WRX. 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.