The picture doesn't really help either. I'd upload a different one but every time I try -- either from my hard drive or a URL -- I get an error saying it's too large. Since it's less than 100k that seems pretty silly, but I can't get past that forum issue for some reason.
Here's another hint though... it's hard to see but the grill cover is round, and the port is downfiring. This may be the only inexpensive subwoofer configured that way.