Patented Genius Power Control Real P4 Case with outstanding shape Mainboard: Compatible with ATX, microATX & Baby AT formats Super Capacity: With 4 x 5.25" FDD spaces & 2 x 3.5" FDD spaces & 1 x 3.5" HDD space. Tool-Free design for opening the side-covers: The side-opening design to offer less damage upon installation. Better Ventilation for System: With Two Optional Spaces for Second Fan. No Hand Cutting: All beveled metal edges to prevent injury. Detachable 3.5" FDD/HDD Bracket: Offer better solution for assembly & maintenance Metal Structure with extent depth to support four 5.25" device when use P4 Full size M/B (maximum size: 12"x 9.6")