This new old stock-testing 5Z3 tube was tested in our Jackson 648 and measured: 118 / 118 (RCA stenciled on base with code CY) Good range is from 70 - 130 on the Jackson. Black hanging plates and tight on base with no debris or rattling and tests 118% / 118% out of 130 scale. Tube ships via United States Postal Service (USPS) Ground Advantage with tracking for domestic U.S. sale; Priority Mail is an option if you wish your package delivered quicker. International orders ship via International Shipping service. Package weighs twelve ounces (12 oz). Check out other tubes in my store for your equipment needs. Combined shipping always welcomed. TUBES ARE GUARANTEED GOOD AND IN WORKING ORDER AT SHIPMENT. TRANSIT VIA POST CAN DAMAGE TUBES. THIS IS NO FAULT OF OURS BUT THE THIRD PARTY ENTITY THAT IS DELIVERING ITEM(S) TO YOU, I.E, USPS, UPS, FEDEX, YOUR NATIONAL CARRIER IF INTERNATIONAL, ETC. PLEASE INSURE THEM! WE CANNOT GUARANTEE FAILURES ON YOUR EQUIPMENT AFTER POWER UP AS THERE IS NO WAY TO ASCERTAIN HOW TUBES WILL INTERACT WITH YOUR ELECTRONICS; NOR IS THERE A WAY TO DETERMINE WHETHER THEY MAY HAVE FATAL FLAWS IN TUBES THEMSELVES! THESE ARE USED VACUUM TUBES AND TIME MAY HAVE TAKEN A TOLL ON THEM OVER THE MANY YEARS SINCE THEY WERE MANUFACTURED. WE CAN ONLY TEST FOR THE PARAMETERS MENTIONED ABOVE IN ONE OR MORE OF THE FOLLOWING EQUIPMENT WE USE FOR MEASURING: HICKOK 600A, HICKOK 800, MAXI MATCHER MAXI MATCHER 2.