TheMullard 0C2 tube was made inUSA, theNational 0B2 was made inHolland, theNational 0A2 was made inGermany, and theAmperex 0B2 was made inGreat Britain. (the Amperex box is missing the top flap).
TheMullard 0C2 tube was made inUSA, theNational 0B2 was made inHolland, theNational 0A2 was made inGermany, and theAmperex 0B2 was made inGreat Britain. (the Amperex box is missing the top flap).