BUSTRONIC 6U and 7U VME64x high performance backplanes come in more than 30 slot sizes and hundreds of standard configurations, including a range from 2-21 slots. With various power, connection pintail size, shroud, P0 connector, and other options there are hundreds of standard configurations available. The 7U backplanes have an extra 1U of height for extra power bugs to accommodate higher power requirements. In some configurations, this taller backplane acts as an air baffle to redirect the airflow path to aid cooling. In other chassis designs, the 6U height is required due to space restraints or airflow considerations.