*****SELLING WORLD WORLWIDE*****>>>>PAIR,VINTAGE,NEW STC / ITT S11E12,POSSIBLE DIRECT PLUGIN FOR 6L6GC or WE350B.MADE IN UK in the 80’s.Same specs as 12E1 without top cap but Better specs than RCA 6L6GC,,WE350B.WAY CHEAPER THAN USED US MADE 6L6GC or WE 350B TESTED AS KT 88 WITH 12 BIAS.>>>> HAVING A MINIMUM OF; 68 & 69 usiemens AND 44 IS MINIMUM.WITH NEWLY DAN NELSON CALIBRATED LORENZ TV7.>>>>SPECS AVAILABLE UPON REQUEST****** MY WORLDWIDE SHIPPING IS BY USPS MAIL. ******PLEASE CHECK MY OTHER COOL AUDIO STUFF.. *****QUESTIONS ARE ALWAYS WELCOME.