Power for the harddisk is delivered by an external PSU. This is necessary, because USB is specified to max. 500mA.
This button has to be pressed to open the enclosure. No screwdriver required.
Inside you will find some empty space for your 3.5" HDD and a small PCB which has the controller chip on-board. The cable is a standard IDE cable, if you lose or break the cable you can just use any regular HDD cable.
Supporting Ethernet and USB at the same time does not seem to be so easy. The PCB is packed with ICs.
When the unit is powered on, the analog VU meter is lit up in a nice blue. The meter's needle moves with harddisk activity.
One side has the power switch and all the external connectors for USB, Ethernet and power supply.
To make sure that your HDD is placed safe inside the unit, this foam pressed down on the HDD when the lid is closed.
For additional visualization three LEDs are installed. Left shows if Ethernet is connected, middle whether the interface is 10 MBit or 100 MBit. The LED on the right is lit when USB is active.