The MB982SP-1S fully encloses the drive - when the lid is closed, there's no hollow sides. It's made of 1mm thick SECC steel and is fairly heavy on it's own. As you can see from the pictures below, Icy Dock has really over-done it with the steel chassis - there's no doubt that this thing really is military grade like they say it is.
The top, front, back and bottom of the MB982SP-1S all have some ventilation slits punched into them. Although these aren't so much a concern for the zero heat SSD's, they will definitely help a mechanical drive breath a little better when fully enclosed.
Screw hole placement on the chassis is an exact mirror of what you'd find on a 3.5" drive. There's three holes down either side, and four on the bottom. This should ensure perfect compatibility with any device or chassis you want to install the MB982SP-1S within.
Around back are the external SATA connectors.