UPD extreme duty, double Nachi bearing, 105mm/ 50mm idler assembly and relocation bracket kit for the 2009 and up CTSV Cadilac / 2012-up ZL1 Camaro. The upper 105mm idler will add extra belt wrap for the supercharger pulley and help eliminate belt slip. The lower 50mm idler will allow for current and future clearance for larger lower crank balancer changes and this kit can allow up to a 10.75″ crank ring. The UPD relocation kit will allow for more belt wrap and larger crank rings than any other kit on the market. All parts are made and machined in the USA and use only the best Nachi bearings to handle heavy supercharger loads and speeds. The UPD idler relocation kit is a lot lighter and reduces idler rotational weight by 1 lb and the whole kit is 2.2 lbs lighter than the OEM assembly shown in the second picture comparison. This kit can be used on stock cars to help with supercharger belt wrap, reduce weight, increase idler durability and plan for future mods.