NOS in original boxes. 1950's vintage. Perfect for old Fender tweeds or anything that uses 5881s.
Very rare! Good original boxes.
Pre STR type from the 1960s. Lightly used, test as new. Various colors of Sylvana logos on the bases and glass. Matched pairs may not both have identical markings but are identical in structure and electrically.
Lightly used, tests as new. Same UK made KT66 as Genelex, Gold Lion, GEC etc which were ALL products of the MO Valve company in England. This one is branded RSD. Gray glass, brown base.
NOS in original boxes. These can be used anywhere 5881s are used.
NOS in original military boxes marked "inspected 12/1955". Lower wattage than 6L6GCs (19 watts). Perfect anywhere 5881s, 6L6Gs or EL37s are normally used. Plate voltage upper limit is spec'd at 450V in class AB1 (most guitar amps and many audiophile amps) circuits. Great in tweed Bassman and other tweed or tweed style 5881 or 6L6G amps.
Test GOOD but not quite good enough for me to list them as ANOS.
Tall bottle. NOS in original boxes. Various labels and boxes. One electrically matched pair labeled and boxed as National and Mesa.Identical dual getter STR tubes, different labels and boxes.
JAN (Joint Army Navy) military version in original and white boxes.
"Almost NOS". Used, test as new. One matched pair in stock.