This case has four 5 ¼” bays, two external 3 ½” bays and five internal 3 ½” bays, with four of them located inside a removable hard disk drive cage, see Figure 14. All bays from this case use screwless installation mechanisms that really don’t require screws, except if you wish to install hard disk drives on the two external 3 ½” bays. As you can see on Figure 14 they use a different mechanism that isn’t compatible with hard disk drives. If you want to install hard disk drives there you will need to remove the plastic mechanisms and use regular screws. The maximum number of hard disk drives you can have with this case is six or seven, if you don’t have a floppy disk drive.

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Figure 14: Bays available on Unicorn.

The hard disk drive cage can be removed by removing a thumbscrew and pulling a lever. To remove it you first need to slide it to a 45º angle – which may help you to install hard disk drives without needing to remove the cage from the case.

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Figure 15: Sliding the hard disk drive cage.

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Figure 16: Hard disk drive cage outside the case.