Now it was time to install my Western Digital Caviar Blue HDD. There are twenty anti-vibration rubber plugs provided of which four need to be fastened to the side of any 3.5″ HDD using the supplied screws. Installation involved attaching the four anti-vibration rubber plugs to my HDD then slotting the HDD into the tool-free HDD mounting tray (quiet a clever idea and not one I have seen before!). A bolt is then screwed into the side of the HDD to keep it in place.