I thought they included that to make the product appealing for notebook users, but as it doesn't seem to have a slimline SATA connector on the back, it can only really be used in desktop cases with a slim ODD slot. Still, a very cool product, it could motivate other case manufacturers to also include a slim ODD slot just to let users expand the IO. Before this I/O add-ons were only available for 3.5" or 5.25" bays, so pushing for that in the Slim 5.25" slot makes a lot of sense.
Silverstone are really pushing things in the SFF market.