D. Scott Chatfield
>I think the extension was a box to put an extra knuckle.
Perhaps, but it seems a little narrow and way too deep to hold a knuckle. It would be very awkward trying to lift one out.
I think it holds ATS equipment. Notice the hinges on the outer edge and how tightly the lid seats. No evidence of being scraped while extracting a knuckle.
Perhaps the answer is in the archives.....