The top and sides of the unit are one piece of bent steel that is held on with three screws at the back of the housing. I decided to remove the cover to have a bit of a look around inside. The first image shows one side where a black sheet of steel isolates the drive cage, and we can see the 80mm exhaust fan off to the right. The next image was taken looking down on the housing, where we can see inside the drive cage, with the device's motherboard off to the bottom with the fan's power lead connected to a header. The final image shows the other side of the unit where a thick sheet of black plastic is installed over the motherboard to protect from shorting out against the steel of the cover.
Two notches in the plastic sheet placed over the motherboard allow you to access the installed system memory. Seeing that there were two memory slots, I was hopeful that the 2GB of memory was achieved with one module, leaving one slot open for an easy upgrade. Instead I found that there were two 1GB sticks of DSL branded DDR3 memory rated for 1866MHz.
The next row of images shows a pair of Western Digital 4TB SE (WD4000F9MZ) drives being installed in the drive trays. ASUSTOR provides screws to mount either 2.5" or 3.5" drives, but using the larger form factor just makes more sense to me in terms of capacity and price. You use four screws to mount each drive to its tray, and then you simply slide it back in to the NAS server and latch it in place.
