(!!!!!) (Best Tungsol Pair) 5881 Tungsol 1960-1967 like new and used - same build (66.2ma and 66.5ma)
(!!!!!) (Recommended Pair) 5881 GE Canada NOS 1966-1967 (65.2ma and 68.5ma) (same build as Tungsol)
(!!!!) (Best Value Pair) 5881 Tungsol used/75% 1957 (54ma and 59ma) (Gm 75%)
(!!!!) (Best Value Pair) 6L6WGB=5881 Sylvania NOS and like new same build 1970's (74ma and 75ma)
(!!!!) (Good Value Pair) 6L6WGB=5881 Sylvania and Philips JAN black base 1979-1986 (72ma and 73.4ma)
(!!!!) (Recommended Pair) 6L6WGB=5881 Sylvania NOS same build 1980 era (81ma and 84ma) (same Gm)
(!!!!) (Recommended used pair) 5881 Tungsol used/good 1960's (63.2ma and 66ma)
(!!!) (Good Value Pair) 6L6WGB=5881 Sylvania brown base NOS and used/like new (59ma and 61ma)
(!!!) (Good Value) 6L6WGB=5881 Russian made wafer-base used/good 1990's (58ma and 62ma)
(!!!) (Recommended Pair) 5881 Sylvania black base NOS 1970's same build (65ma and 67ma)
(!!!) (Recommended Pair) 5881 Sylvania black base NOS 1979 same build (73.2ma and 74ma)
(!!!) (Recommended Pair) 6L6WGB=5881 Sylvania black base NOS 1980-1987 same build (70ma and 72.8ma)
(!!!) (Recommended Pair) 6L6WGB=5881 Sylvania black base NOS 1980-1987 same build (86ma and 91ma)
(!!!) (Recommended Single) 5881 Tungsol branded RCA used/very good 1960's (70ma)
(!!!) (Recommended Single) 5881 Tungsol rebranded Sylvania 1960 era (77.5ma)
(!!!) 5881 Tungsol branded Raytheon used/good 1950's (54ma)
(!!!) 5881 Tungsol used/good 1957 (58ma)
(!!!) JAN-CTL6L6WGB=5881 Tungsol used/good 1954 (60ma)
(!!) (Recommended Single) 5881 GE Canada NOS 1970 (73ma) (same build as Tungsol)
(!!) (Recommended Single) 5881 GE Canada NOS 1970 (81ma) (same build as Tungsol)