This bracket is required when using a 9.17" or larger diameter lower crank pulley. The relo bracket is designed to move the factory lower idler to clear the larger crankshaft pulleys. DMS has taken it a step futher and moved the upper idler mounting point another 5mm adding belt wrap to the upper supercharger pulley. This relo combined with the DMS 100mm idler will provide the most belt wrap available to the LSA market.