Old stock. The tubes are new and never used
Direct drop in Upgrade for stock Chinese 6J1. Fully Bench tested
Best 6J1 upgrade valves available
Same Date Codes
"Voskhod" factory (rocket logo)
OTK marked
We test our tubes from this type on High-End Military Tube Tester:L3-3
Measured parameters attached to each tube, difference < 3%
on the photo shows an example of tubes with parameters
Lot of 4 (Matched & Balanced Quartet)