Features:
The MB453 is the size of two optical drives stacked on top of each other and it takes up two full 5.25" drive bays in your computer case. The multi-bay back plane module itself holds up to three 3.5" SATA drives installed in hot swappable trays. Both SATA I and SATA II types of drives are supported.

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The tray only makes contact with the front and sides of your hard drive. With some other hot swap enclosures on the market the hard drive plugs into the tray and then the tray plugs into the back of the enclosure. With the MB453, the plugs on the back of the hard drive plug directly into connectors on the back of the enclosure. The plugs are then routed to the connection panel on the rear of the enclosure. From there, you can easily plug them into SATA ports on your motherboard. This method uses a direct route from the drive to the motherboard so the enclosure itself is practically invisible in terms of the data stream and won't affect the data transfer speeds.

  
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Cooling to the hard drives is provided by an 80mm exhaust fan attached to the back of the housing. Since the front of each drive tray is grilled, air is very easily taken in and washed over the drives. The fan housing itself is clipped on, making it a tool-less design. This being said, the fan housing is also hot swappable. If the fan were to ever fail while in use you can install a new one without shutting down the drives. I have a few minor complaints about this fan system though. The plastic housing that the fan is in was fairly hard to remove by hand and took some effort to take it off. For those trying to do that with the unit installed in a running computer, it could be impossible. You're probably going to have to shut down the computer and possibly even remove the MB453 if you want to change out the fan, plus, I've never seen a fan fail instantaneously so you should have lots of time to arrange this repair anyway. The other thing I noticed is two of the plastic fan clips have metal connectors on them which go into plugs on the circuit board behind. These are power and data plugs for the fan which is basically wired right on to the housing. If you to want to remove this fan you'll want to have some soldering skills as well as be able to identify proper power and data cable hookup wires on the fan. Personally, I think any future revisions of this should use a standard three-pin fan connector. This would enable the fan to be replaced by any off-the-shelf fan bought at any computer or electronics store. Since three pin fan connectors also carry a data line for fan monitoring it would interface perfectly with the MB453's ability to monitor the fan incase it fails.

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