(!!!!!) (BEST SYLVANIA PAIR) 6550 Sylvania welded plates branded RCA 1978 low hours/like new (124ma and 130ma)

1 matched pair) 6550 Sylvania welded plates branded RCA 1978 low hours/like new 1 tube) 124ma Gm=10,200 1 tube) 130ma Gm=10,100 Good NOS Ma range 125-140ma Good Gm range 10,000 - 11,000 Recommended for - ARC VS 110 and other ARC amps- Audio Research Reference 3 line-stage power supply - Rogue 90- VTL amps; MB300, 450, many others- Gibson guitar amp- McIntosh 275- Beard P100 MKII 1984- Cayin A-88T