The windowed side panel for all Silent Base PC cases The innovative side panel with double-glazed window fits all cases of the be quiet! Silent Base series and offers an excellent view inside your PC. The polycarbonate window is scratchproof and impact resistant as well as sound-absorbent. A cavity of 9mm between the two panes of the window results in superb noise insulation. In addition, the side panel's window is fitted with colored rubber seals in black, orange or silver, which further inhibits the emanation of sound and vibration.