(!!!!!) (BEST Pair) ECC81=12AT7 Mullard UK NOS 1970-1973 (9.0/9.2ma and 8.8/9.8ma)
(!!!!!) (Recommended Pair) ECC81=12AT7 Mullard UK NOS 1966-1972 (9.5/13.0ma and 9.7/11.5ma)
(!!!) (Good Value Pair) ECC81=12AT7 IEC Mullard used/good 1967 (6.8/7.0ma and 7.0/7.2ma) (Jolida, Fender)
(!!!) (Recommended Single) 12AT7=ECC81 Mullard branded Raytheon NOS 1972 (11/13.2ma)
(!!) (Good Value Single) 6201=12AT7 Valvo Germany rebranded Philips SQ 1970 (6.8/7.8mA)
(!!) 12AT7 Knight by Mullard NOS 1966 (8.8/9.4ma)
(!!) CV4024=12AT7WA Brimar NOS square black plates 1968 partially faded printing (7.8/10.4ma)
(!!) CV4024=12AT7WA Brimar NOS square black plates 1973 (11.2/17ma) (high Ma and Gm)
(!!) CV4024=12AT7WA Brimar NOS square black plates 1975 (9.6/14.4ma)
(!!) CV4024=12AT7WA Brimar NOS square black plates 1976 (7.6/8.2ma)
(!!) CV4024=12AT7WA=12AT7 Brimar UK NOS square black plates 1962 (8.6/13.6ma)
(microphonic single) 12AT7 Philips Miniwatt made in Hamburg, Germany by VALVO NOS "D" getter halo 1959 (8.8/10.2ma)
12AT7=ECC81 Mullard low hours/like new 1970 (8.0/8.4ma)
(!!) (SINGLE) M8162=12AT7WA Mullard UK copper grid posts NOS 1963 (9.2/13.5ma)
(!!!!!) (slightly microphonic Valvo Single) E81CC=6201=12AT7 Valvo Hamburg Germany rebranded Philips Holland SQ 1973 (9.4/9.8ma)
(!!!!) (Best Brimar Single 1967) CV4024=12AT7WA Brimar NOS square black plates 1967 (11.2./11.4ma)
(!!) (Best Brimar Single) CV4024=12AT7WA=12AT7 Brimar UK NOS square black plates 1967 (10.2/11.4ma)
(!!!!) (Best Brimar Single) CV4024=12AT7WA Brimar NOS square black plates 1975 (13.4/13.6ma)
(!!) (Recommended Single) CV4024=12AT7WA=12AT7 Brimar UK NOS square black plates 1965-1967 (10.4/9.0ma)
(!!) (Recommended Single 1956) CV4024=12AT7WA=12AT7 Brimar UK NOS square black plates "square" getter 1956 (9.5/10.8ma)