6B7 RCA Emerson NOS 1940's
6B7 Sylvania engraved base tests like new 1930's
6D6 Sylvania NOS 1940's (2 in stock)
6D6 Sylvania NOS small 1/8" glass chip inside tube at bottom
6SQ7GT Fonoco by Sylvania used/strong 1951 (1.1ma and Gm=1100)
6V6GT GE Delco used/good crack in base 1952 (36ma)
