(!!!!) (Best Overall Single) GZ37 Mullard UK NOS 1966 (52/40 and 52/40) 1% section balance
(!!!!) (Best Pair 1966) CV378=GZ37 Mullard NOS 1966 (51-51/40 x 2 tubes) 1% matched
(!!!!) (Best Pair) CV378=GZ37 Mullard NOS 1966 (50-51/40 x 2 tubes) 1% matched
(!!!!) (Best Single) CV378=GZ37 Mullard UK NOS 1966 (53/40 and 54/40)
(!!!!) (Best Single) CV378=GZ37 Mullard UK NOS 1967 (50/40 and 50/40) 1% section balance
(!!!!) (Recommended Single) CV378=GZ37 Mullard UK NOS 1967 (52/40 and 54/40) 1-3% section balance
(!!!!) (Recommended Single) GZ37 Mullard UK NOS 1967 (50/40 and 50/40)
(!!!) (sold out) E810F=7788 Philips Miniwatt SQ Holland gold pins used/very good 1965-1967 (38ma and 39ma)
6FG7 US Brands NOS (6 in stock)
7788=E810F Amperex PQ USA NOS 1969-1970 (33ma)
E55L=8233 Mullard branded Philips NOS 1967 (59ma)
JAN-7788 Amperex USA NOS 1986 (54ma)
