Pair of RCA JRC 6189 12AU7/WA vacuum tubes matching date codes  
Tested with a calibrated TV-7D/U tube tester.
Calibration by Daniel Nelson.
Tested at: 92/93 plate current 11.4/11.3 
                 93/93 plate current 11.2/11.5
Average new: 93/93
Minimum good: 56/56 
The minimum is equal to 65% of the life of the tube.
Tested for shorts and gas.
Matching date code: 37- 58-43 box dates 10-58
Construction: triple mica short black plate 
Glass: clear with chrome top
Base: nine pin
30-day free return.
We combine shipping $1.00 for each extra tube purchase.
Your items will be packed very well and shipped promptly.
Always glad to answer any questions.
Thanks for looking!