What makes our Pro Select discs different from a standard thermal hub printable disc? These discs feature a metalized layer beneath the print surface that extends all the way to the center hub. This provides a perfectly uniform print area with no changes in brightness or contrast near the center ring. Of course, these discs are also 52X rated with an 80-minute / 700MB capacity for all of your audio and data storage needs. When you combine all of these factors, you have a disc that is truly "Pro Select!"