Precision made two piece rocker covers with separate rocker arm carriers. These kits will guarantee a very rigid and stable rocker carrier and provide hassle free installation. These kits are die-cast aluminum from high quality aluminum alloy and precision machined using the latest CNC technology. The complete kit includes top rocker covers, lower rocker covers, inner rocker arm carrier blocks, gaskets, seals and hardware for both the front and rear cylinder. Rocker covers are clearanced to permit valve lifts up to .640" using aftermarket valve springs packages. Fits all Twin Cam models 1999 thru 2017 and a must when installing a S&S compression release kit.