Marched pair of 6S2S (6C2C) tubes. Tubes were measured on the precise L3-3 (Л3-3) tube tester. It is direct replacement for the american 6J5GT and VT-94D tubes. Manufactured in USSR during the 60's. Service life - not less than 2000 operating hours. Will be delivered in original boxes - measured parameters included. Condition: NIB.