This is primarily intended for new installations of osCommerce 2.2 MS2, but can also be used (with some SQL work) with existing installs. It adds the ability to specify a prefix to the tables of a given osCommerce installation. This way, if you only have one database available (common in many shared hosting environments) you can still have multiple instances of osCommerce. Extract these files into your osCommerce installation before running the configuration for the first time.