Features1. Sliding drive-track: Easily sliding-in assembly without screwing.2. Expandable accommodation of HDD: At most 7* HDD for expansion.3. Easily removable HDD cage: HDD cage which is able to accommodate with 5*3.5" HDD and enhance performance on removing and installation.4. 'Ideal Hook' on the side plate for easily arranging wires without messing around inside case.5. Humanistic accessing interface of USB port + Audio I/O + IEEE1394 on the side of panel.6. cooling fan for HDD: Well performance with 1*8cm fan enhances airflow-in via vents to efficiently cooling down HDD.7. Selective size of 2nd. fan on the rear: 12cm, 9cm or 8 cm.