2. 3 x 3.5" Rear Hot-swap SAS / SATA Drive Bays
3. 4 x 3-Pin 40x40x56mm Cooling Fan
4. With Universal I/O (UIO) Card:
3 x Full-height, Half-length I/O
3 x Low-Profile Expansion Slots
Without Universal I/O (UIO) Card:
4 x Full-height, Half-length I/O
3 x Low-Profile Expansion Slots
5. Power Switch & 6 LED Indicators
6. Front I/O Access
7. Only 17.7" Compact Chassis Depth