Sylvania 5763 vacuum tubes new old stock  
Tested with a calibrated TV-7D/U tube tester.
Calibration by Daniel Nelson.
Tested at: 48 48 
Average new: 58
Minimum good: 35 
The minimum is equal to 65% of the life of the tube.
Tested for shorts and gas.
Date code: -
Construction: gray plate square getter
Glass: clear
Base: 9 pin
Not tested for sound, noise or performance quality in any type of equipment.
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!