One vintage 1930 Western Electric 211E vacuum tube. This was manufactured with splits in the bakelite base between the four contacts. See photos. It has 2-15-30 engraved on the base. This appears to be post manufacture by someone. Filament continuity tested as in photos. My dad saved lots of unique vintage tubes and was a ham since 1932. Since this is a pricy tube I have oversized the box in shipping so I can super pack this tube.