This case has four external 5 ¼” bays, one external 3 ½” bays and three internal 3 ½” bays. You need to use regular screws with the 5 ¼” and the external 3 ½” bays, but the hard disk drive bays come with thumbscrews that use rubber rings to prevent the vibration produced by the hard disk drives from propagating to the chassis, i.e., this case comes with a noise prevention mechanism for the hard disk drives.

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Figure 10: Hard disk drive cage.

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Figure 11: Thumbscrews and rubber rings for installing hard disk drives.

After you slide the hard disk drives into their bays, you must lower a small bar that will lock the hard disk drives in place and fasten this bar with a thumbscrew.

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Figure 12: Hard disk drive installed. You need to lower and lock the small bar on the left to lock the hard drives in place.

The external 3 ½” bay may be used for installing a 3 ½” or even a 2.5” hard disk drive or SSD unit, but in this case normal screws must be used.

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Figure 13: External 3 ½” bay removed from the case. Notice the holes on the bottom part for installing 2.5” devices.