Scratch-Less Disc Spindle of 10 Discs Aero-Bump - The term comes from the 2 physical characteristics which are 20 protective Bumps, around the outer edge creating a gap to prevent data surface contact and damage, and Aero from the aerodynamic shape of the bumps. Safety-Shield - Working with leading designers in optical discs, the Invisible Safety Shield was developed with an optical clear scratch-preventative polymer that is added to increase the disc's surface strength to prevent scartches and scuff. It almost eliminates all damages created from usual use and handling. Ez-Up-Edge - Scratch-Less Disc's unique characteristic that automatically guides your fingertips under the disc's outer edge which allows you to pick up the disc with ease. Universally Compatible Disc (UCD) - Scratch-Less Disc Technology is compatible with 99% of all home audio, PC, car audio and other recording and playback devices. You don't need to change of modify any of your equipment to use this disc. UCD assures universal compatibility of the discs. Safety-Gap - With the Aero Bumps feature, Scratch-Less discs are created with Safety-Gaps to prevent contact and damage when placed down. Part of the safet-handling feature.