Philips/Amperex 12AT7/ECC81 vacuum tubes with grey ribbed plates, copper grid rods, supersized angled D-Getter with bottom date codes.Labeled as "Mullard/Made in Holland". Extremely rare very early production tubes. Several tubes are available for matching by pair/quad etc. $75 for one tube. The triangle code on the bottom means that they were made by Philips/Amperex in Copenhagen, Denmark. Date Code at the bottom of the tube: Triangle B TkP
Made in February 1954: ***Extremely Rare, Very Early Production*** Tested on my Calibrated Hickok 539C tube tester. No shorts, leakage, or gas. Minimum good on this tester is 2500 and all tubes test over 4000 (NOS testing). Also, tested in my preamp and work perfectly. Individual test measurement results for each tube will be provided to you upon your order. Full money back guarantee! USPS Priority Mail shipping with tracking within US will be flat $7.50. Payment by check or money order (no Paypal please). Local pickup with cash is welcome. I have over 400 100% positive feedback on Audiogon with the same member ID - "sojs", so buy with confidence. 
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