Old stock. The tubes are new and never used
"Uljanovsk" factory
Same Date from 1970's (from same batch)
Tested and Measured Quad G-807 (Г-807) Beam Tetrode
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 the tubes with parameters
Lot of 4 (Matched & Balanced QUAD)