Biersach & Niedermeyer: a brand name that itself sounds as though someone could easily mistake it for being of German origin if not for the "Milwaukee WI USA" stamped directly underneath.
A band straight in front of the ports can only serve to diminish the output, and I'm sure at least a few on the design team had their doubts. I think more than anything it served to act as a convenient protective ring against nesting critters.
I'm placing my bets on a CLM or some other British-standard unit made in Canada. Darn, I just looked at the test schedules, what an inconvenient time to venture two hours out of town for. xD