This new old stock-testing Sylvania JAN CHS 5U4G / 5U4G rectifier tube was tested in our TV-7/U and measured: 58 / 60 (JAN CHS 5U4G Made in U.S.A. Sylvania stenciled on base with code 050; 5U4G stenciled on glass) Minimum is 40 (65%); NOS-Testing is 54+ (90%+). This tube tests 97% / 100%. Pair have black plates and a bottom D getter. Tube is tight on base as a previous owner glued it; glass debris rattling in base but does not effect performance. Sound tested in a Dynaco Stereo 70 amplifier and performed excellent (see pics). Tubes ships via United States Postal Service (USPS) Ground Advantage with tracking for domestic U.S. sales. International sales ship via International Shipping service. Package weighs twelve ounces (10 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: TV-7/U, JACKSON 648 MAXI MATCHER 2.