(!!!!) (Single 1950's) 12BH7A RCA branded Westinghouse narrow black plates NOS "U" getter mid-1950's (10.6/7.4ma) (1st series made)
(!!!!) (Single 1955 era) 12BH7A RCA narrow black plates used/very good "U" getter halo 1955 era (8.6/10ma) (1st series made) (rare)
(!!) (Good Value Pair) 12BH7A RCA gray plates used/good 1960's (10.4/82.ma and 9.4/9.5ma) (close Gm)
(!!) 12BH7A RCA gray plates used/good 1960's (8.0/11.2ma)
(!!) 12BH7A RCA gray plates used/good 1970 era (8/9ma)
