Old stock. The tubes are new and never used
"Reflektor" factory
"OTK" marked
White (chromed) pins
Direct replacement for 6U1 / ECH81 / 6AJ8 tubes
Same Date code - 1984 (from same batch / box)
Tested and Measured Pair 6I1P-EV
tubes were tested in triode mode
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 2 (Matched & Balanced Pair)