Rackmount eSATA External HD Enclosure

Looks like this is a SansDigital EN104L+BXE.

Product page here: http://www.sansdigital.com/en104lplusbxe.html

Video illustrating the web interface from another SansDigital NAS:
https://www.youtube.com/watch?v=EScAjT95PV8

Next cheapest price I found for this is $500.