National Union NU 14X7 Vacuum Tube NOS NIB September 18 2024 They have engraved / hot-stamped

They have engraved / hot-stamped bases

new in box GE 12X4 tube -- and three others just like it -- tested to spec on our Paul Hart-calibrated TV7/U

These tubes have four shiny copper support rods

This matched trio of GE 12HG7 tubes was tested on our Paul Hart-calibrated TV7/U (on the 12BY7 setting) for shorts

National Union NU 14X7 Vacuum Tube NOS NIB September 18 2024 They have engraved / hot-stampedThis new old stock, new in box National Union 14X7 and another just like it tested to spec on our Paul Hart calibrated TV7 U. Etsy will indicate how many are available in this Dutch Auction. WE HAVE SCORES OF THOUSANDS OF VACUUM TUBES. IF IT'S NOT LISTED, WE MAY HAVE IT. PLEASE ALSO SEE OUT ETSY SISTER SITE "LOWTECHTWOO" AND OR CALL OR TEXT US AT 202 372 6931 IF YOU DO NOT SEE WHAT YOU NEED OR HAVE ANY QUESTIONS. 1. MOST FORMS OF SHIPPING EXCEPT MEDIA