NOS NIB Sylvania (Zenith Label) USA 2B7 Silver Mesh Plate In Can Vacuum Tube

Tube Type / Number: 2B7
Actual Brand*: Sylvania (Zenith Label)
Printed Brand: Zenith
Quantity of Tubes: Single
Plate Construction: Silver Mesh
Getter Construction: Bottom D Foil
Country of Manufacture: USA
Visible Date Codes: M2R
Lettering Condition: 100 Percent
Year Made:
Mica Spacers: 2
Smoked Glass? No
Engraved Base? No
Boxes Included? 1 Box - Original
Notes: Was Sealed in Cannister

Gm Test Results: 46/46/46
Minimum Good Value: 25/40/40
NOS Test Value: 41/45/45
Life Calculation: 100+% (where 65% = fail)

Tests as NOS?: Yes
True NOS?*: Yes

** Please note, many tubes will test NOS but will actually have a few hours of use on them. A truly NOS tube will have excellent getter flashing condition, no dirt/grime, usually in the original box, and no filament deposits. If a tube is listed  as "tests NOS" but is listed as "not True NOS" please expect the tube to have a small amount of use *

All tubes have been tested using only the best tube testers. We have a large fleet of tube testers, and every single one of them has been calibrated within the last year by industry experts. We mainly use the Hickok TV-7D/U, but occasionally we may use a Hickok 539, 533A, or 600A.