As mentioned this case has two external 5 ¼” bays, on external 2 ½” bay for a removable hard disk drive enclosure and two internal 3 ½” bays.

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Figure 11: External 5 ¼” and 2 ½” bays.

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Figure 12: Internal 3 ½” bays.
Unfortunately this case doesn’t use anti-vibration mechanisms for the hard disk drive, which is a desirable feature for home theater PCs.
On Figure 13 we show the hard disk drive enclosure that comes with the case. It is targeted to 2 ½” parallel ATA (PATA) laptop hard disk drives – pay attention because you can easily find 2 ½” SATA hard disk drives around. Bgears sells a printed circuit board for SATA hard drives for USD 9.99 (or USD 15.99 if you want the full enclosure instead of just the printed circuit board). Three and a half-inch (i.e. desktop) units don’t fit the enclosure.
Externally the enclosure is connected to the PC using a USB port (both PATA and SATA versions), so you can’t use this enclosure to hold your main hard disk drive, only a data hard disk. The case comes with a USB cable to allow you to install your data hard disk drive to any PC as an external device.

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Figure 13: Hard disk drive enclosure.

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Figure 14: Hard disk drive enclosure.