(!!!) (Best Pair) JAN-CRC-808 RCA NOS 1945 (52/36 and 52/36)
(!!) (#4 Type 30 PAIR) USN-CRC-30 RCA NOS 1940's "L" bracket (2.4ma and 2.8ma)
(!) (Recommended Pair) USN-CRC-6AC7 RCA mid-1940's used/test like new (10.6/11.0ma)
0D3 Tungsol NOS 1950's slightly tilted glass (argon)
VR-150=VT-139=0D3 Sylvania NOS 1940's (argon)