RFT 12AX7 No matter how these are branded (Amperex, Positron, National, Siemens,the list goes on and on) RFT 12AX7 tubes are of amazing quality and have an exceptional tone. These tubes were manufactured in East Germnay by the RFT company. They are renown for their tone in high gain guitar amps like the Diesel “Herbert” , Carmen Ghia, Dr Z Maz Jr. and Marshall’s, these absolutely smoke!. We can now offer unprecedented matching as we got in a supply of over 100 pcs! Now just $59.99 per tube!