6BW4 Sylvania black plates used/good 1954-1955
6BW4 Sylvania branded GE black plates 1974 slightly tilted glass (54/40 and 54/40)
6BW4 Sylvania branded GE gray plates 1961 (53/40 and 55/40)
6BW4 Sylvania branded RCA black plates NOS 1964 (54/40 and 56/40)
6BW4 Sylvania branded RCA black plates used/good 1960's (52/40 and 52/40)