(Display tube) 201A Volutron brass base - does not work - in good condition - 1920's
(picture only) 01A RCA engraved base NOS 1930's
01A National Union NOS 1940's (3.1ma)
01A PHILCO engraved base used/tests like new 1930's (3.7ma)
01A Sylvania engraved used 1930's (2.5ma Gm=400)
