(!!!!!) (BEST OVERALL PAIR) EL37 Mullard NOS black base and brown base gray plate same build NOS 1962-1966 (90.5ma and 91.5ma)
(!!!!!) (BEST VALUE PAIR) EL37 Mullard low hours/like new Ma and Gm, gray plate, same build 1963-1969 (75ma and 79ma)
(!!!!) (BEST BLACK PLATE PAIR 1950's) EL37 Mullard UK black plates double "O" getter halos 1957-1960 same build NOS and like new (79ma and 78ma) 1-2% matched
(!!!!) (Best Single 1957) EL37 Mullard black plate NOS (2) upside-down cup-shape getter halos 1957 (74ma)
(!!!!) (BEST VALUE PAIR 1950's) EL37 Mullard black plates used/good 1956-1957 (73ma and 76ma)
(!!) (BEST OVERALL PAIR 1962) EL37 Mullard NOS gray plate NOS 1962 (85ma and 86ma) 1-2% matched
(!!) (Pre-1955) EL37 Mullard branded Philips Miniwatt gray plate like new, small rattle inside base, made before 1955 (81ma)
(!!) (Pre-1955) EL37 Mullard like new gray plate, 1 upside-down "cup shape" getter halo, made on or before 1955 (91ma)
EL37 Mullard black plate used 1957 (63ma)
EL37 Mullard gray plate NOS 1960's double "O" getter halos (59ma)
EL37 Mullard gray plate used/good double "O" getter halos 1960's (60ma)
EL37 Mullard used 1956 (53ma)
