Vintage “air condition indicator”, black plate is made in bakelite. I found the brevet information on the web, here is a copy to get more information. Bullock air condition indicator filed nov. H j mu ‘m n’ hm\ m v 1125 30554045 so 55 6065 70 75oh iii inventor. Frank bazzoa/a by wwhwcwu/w attorn ey [...]