The MB122 enclosure is quite compact and will fit into a free 5.25" drive bay in any case. There are four holes for a typical installation with screws or other alternative tool-less systems that let 5.25" devices snap in. There is a flap that swings down when the hard drive tray is removed to repel dust from entering the vacant space.
The front of the enclosure has a 2" LCD for exchanging information between the hard drive and the user. The latch that has the Serial ATA logo opens and reveals a key-locking mechanism for drive security.
From the rear view you see the connections that go to your motherboard and power supply, and there is a fan to suck air from the enclosure. You have the choice of a 4-pin or SATA power connector and there is one standard SATA data connection. The dip switch is for Master/Slave operation (On=Master), and the headers have connections for power LED, HDD activity, temperature, and fan failures.
The MB722 looks like the MB122 but has a different front plate and connection. It is also about an inch longer and might create some trouble when trying to install it into mid-tower ATX cases with a large motherboard footprint.
The front of the enclosure is much more stylish with the limited edition, changeable front plate that resembles a Poseidon-like figure. It has the same 2" LCD screen and buttons, but the key-lock is already exposed. The rear looks a little different with the fan on the opposite side and only one power connector (4-pin) to choose from.
