(1) Tested Sylvania 6BN4A Tube Date Code cj ABU Medium Mu Triode 6BN4 A Tube

(1) Tested Sylvania 6MD8 Tube with Box Date Code fd AJD Medium Mu Triple Triode

(1) Tested Sylvania 6JZ8 Tube with Box Date Code hl AAO Medium Mu Triode Pentode

(1) Tested Sylvania 5CL8A Tube Date Code da AGD Medium Mu Triode Sharp Tetrode

(1) Tested Sylvania 6ES5 Tube Date Code AAU High Mu Triode Tube

(1) Tested Sylvania 6J6A Tube 6J6 A Tube Red Letter Medium Mu Twin Triode Tube

(1) Tested Philco 6AF4 Tube Date Code 57-52 Medium Mu Triode Tube Sylvania EIA

(1) Tested Sylvania 6T8A Tube Date Code ab ESO Triple Diode High Mu Triode Tube