6F6G National Union used/good mid-1940's (47ma)
6F6G RCA Cunningham used/good 1947 (31ma)
6F6G RCA NOS 1949 (35.8ma)
6F6G RCA NOS 1957 (42.2ma)
6F6G Tungsol burgundy base NOS 1951 (31.2ma)
