The top of the front panel of the Three Hundred features a front access panel consisting of 2 USB 2.0 ports, audio jacks (headphones and microphone), and a reset and power button.
While the whole front panel appears to be perforated, this is not the case. The covers for the 5.25" drive bays look to be perforated from afar, but with closer inspection we can see that they don't have any holes in them. The area of the front panel that covers the two front 120mm ventilation holes and 3.5" drive bays is actually perforated. In addition, this area is also fitted with a finer mesh material in the back of the panel, acting as a dust filter.
The side panel on the right-side of the case is plain black. The top of the case has a 120mm ventilation hole near the back end. Small hexagon shaped cutouts were pressed out of the panel, all of which form a 120mm square. This manufacturing technique is good from a noise point of view: since the grill is built into the case and is not a separate part, this removes an extra piece that can add vibrational noise.