(!!!!!) (Recommended Single) 6X4 SER = LM Ericsson Sweden "D" getter NOS 1950's (56/40 and 60/40)
(!!!!) (Best Pair) 6X4 SER = LM Ericsson Sweden "D" getter NOS 1950's 1-2% matched (54-55/40 and 54-55/40 x 2 tubes)
(!!!!) (BEST PRICE) 6X4 SER = LM Ericsson Sweden "D" getter NOS 1950's (3 in stock)
(!!!!) (Best Value) JTL-6X4 Tungsol 1950's curved "D" getter low hours/like new reprinted in 1977 (58/40 and 60/40)
(!!!!) (Best Value) JTL-6X4 Tungsol 1950's curved "D" getter low hours/like new reprinted in 1977 (60/40 and 60/40)
(!!!!) (Recommended Pair) 6X4 SER = LM Ericsson Sweden "D" getter NOS 1950's 1-2% matched (53-55/40 x 2 tubes)
(!!!!) (Recommended Pair) 6X4 SER = LM Ericsson Sweden "D" getter NOS 1950's 1-2% matched (54-55/40 and 54-55/40 x 2 tubes)
(!!!) (Best Single) 6X4 Tungsol NOS 1957 "D" getter (54/40 and 57/40)
(!!!) (Best Single) 6X4 Tungsol NOS 1957 "D" getter (57/40 and 55/40)
(!!!) (BEST VALUE SINGLE) 6X4 SER = LM Ericsson Sweden "D" getter NOS 1950's slightly tilted glass (54/40 and 54/40)
(!!!) (Recommended Single) 6X4 SER = LM Ericsson Sweden "D" getter NOS 1950's (53/40 and 54/40)
(!!!) (Recommended Single) 6X4 SER = LM Ericsson Sweden "D" getter NOS 1950's (54/40 and 55/40)
(!!!) (Recommended Single) 6X4 SER = LM Ericsson Sweden "D" getter NOS 1950's (54/40 and 56/40)
(!!!) (Recommended Single) JTL-6X4W Tungsol NOS 1955 curved "D" getter (48/40 and 50/40)
(!!!) (Recommended Single) JTL-6X4W Tungsol NOS 1955 curved "D" getter one section of internal plate bent at bottom (52/40 and 57/40)
(!!!) (Recommended Single) JTL-6X4WA Tungsol NOS 1962 curved "D" getter (55/40 and 60/40)
(!!!) (Set of 77) 6X4 US Brands NOS original boxes 1950-1980 era (set fo 77)
(!!!) JTL-6X4W Tungsol NOS 1955 curved "D" getter halo (45/40 and 52/40)
(!!) 6X4 RCA NOS 1960's faded printing (49/40 and 51/40)
6X4 Arcturus by GE NOS "D" getter 1960 (54/40 and 54/40)
