(!!!!!) (Best GE Pair) 6021 GE 5 Star Rated NOS "D" getter halo 1957 in GE 5 Star Boxes (1-3% matched) (5.5/5.8ma and 5.4/5.9ma)
(!!!!!) (Best Value Pair) 6021 GE 5 Star Rated NOS "D" getter halo 1957 in GE 5 Star Boxes (1-3% matched) (5.0/7.2ma and 4.8/6.6ma)
(!!!!!) (Good Value Pair - for Audio Aero) 6021=CV3986 Mullard UK Mitcham NOS 1969 (4.4/4.6ma and 4.5/4.8ma) (1-3% matched)
(!!!!!) (Recommended Pair - for Audio Aero) 6021=CV3986 Mullard UK Mitcham NOS 1969 (4.8/5.3ma and 4.8/5.0ma) (1-3% matched)
(!!!!) (Best Value Pair) 6021=CV3986 Mullard UK Whyteleafe plant NOS 1972 original boxes (4.4/7.0ma and 4.8/6.0ma)
(!!!) (Best Raytheon Pair) JAN-6021W Raytheon NOS 1972 some extra getter stains on glass (5.0/6.0ma and 4.6/5.4ma)
(!!!) (Good Value) 6021=CV3986 Mullard UK Mitcham plant NOS 1971 (4.2/4.4ma and 4.2/4.4ma)
(!!!) (Recommended Philips Pair) 6021W Sylvania branded Philips NOS 1986 (7.2/8.4ma and 6.8/8.2ma) (Highest mA and Gm)
(!!) (Good Value Pair) 6021=CV3986 Mullard UK Mitcham plant NOS 1971 original boxes (4.8/6.3ma and 4.6/6.5ma)
6021 probably made by EI Yugoslavia NOS 1970's - 1980's (1 pair)
JG-6021 GE black plates NOS 1954 (6.3/6.8ma) (1 single tube)
