This is what some people think they are. Some of them are MS XBOX HD Restore utility disks. They boot, format, etc thew xbox hd.. and restore to factory defaults. (deletes savegames too) It's a RMA Dept System Restore Disk... they use them when people send their units in to be fixed. They rarely check and investigate your box.. they look at the noted problem.. replace parts.. and bot this disk to wipe your drive and place it back to default.