(!!!!) (Best Pair) 5R4GB GE black base NOS 1981 (50-52/40 and 50-53/40 x 2 tubes)
(!!!!) (Best Pair) 5R4GB GE black base NOS 1981 (51-53/40 and 51-54/40 x 2 tubes)
(!!!!) (Best Pair) 5R4GB GE black base NOS 1981 (51-54/40 and 52-55/40 x 2 tubes)
(!!) 5R4GB GE NOS 1983 (54/40 and 56/40)
5R4GYA GE branded Westinghouse NOS 1960's (50/40 and 53/40)
