(!!!) (SINGLE) 412A Western Electric NOS 1968 (52/40 and 52/40)
(!!) (Best Pair 1981) 412A Western Electric NOS "O" getter halo 1981 (53-53/40 x 2 tubes)
(!!) (Best Pair) 412A Western Electric NOS "D" getter halo 1959 (51-52/40 x 2 tubes)
(!!) (Best Pair) 412A Western Electric NOS "D" getter halo 1968 (52-52/40 and 52-53/40)
(!!) 412A Western Electric NOS 1965 (52/40 and 52/40)
(!!) 412A Western Electric NOS 1968 (52/40 and 53/40)
(!!) 412A Western Electric NOS 1969 (51/40 and 52/40)
(!!) 412A Western Electric NOS 1970 (53/40 and 53/40)
412A Western Electric NOS 1981 (54/40 and 54/40)
