6X4 GE like new 1950's "D" getter (54/40 and 54/40)
6X4 RCA "O" getter low hours/like new 1960's (49/40 and 52/40)
6X4W GE used/tests like new 1960 era "D" getter (52/40 and 52/40)
6X4WA GE black plates rebranded National NOS (55/40 and 56/40)
6X4WA GE used/tests like new 1960 era no printing (54/40 and 54/40)
