The Lenovo server 4 x 2.5" SAS/SATA backplane kit is designed to enhance server performance and efficiency. This kit includes essential components such as 2 x drive sequence labels, 2 x top cover support sponges, and heatsinks that support 2U performance. With 4 x 2.5" SAS/SATA backplanes and 8 x 2.5" drive cages, it provides the necessary infrastructure for maximizing storage capabilities in a server environment. Included in the package are also 8 x 2.5" HDD fillers, ensuring proper placement and protection of your drives. For manageability, the kit comes with 2 x MCC CPU carriers and 2 x XCC CPU carriers. Additional hardware like M3 screws is included for installation. This server backplane kit offers a reliable solution for those looking to upgrade or build a server with high storage density and effective cooling.