semi-pro waster said:I could be being dense but I thought the description gave it away "...to dress up the front panel in an Aluminum look. Fits over existing bezel.".
Not all drives match the casing, some people take them from their old computers so they want to make sure that they don't stand out from the case because they are beige and the case is black or whatever. Also most drives have a matt finish and aluminium is smooth so they still stand out slightly without a bezel to cover it.