(1) Tested GE 6KA8 Tube with Box Great Britain Date Code HI Triode Pentode

(1) Tested RCA 6KA8 Tube with Box Date Code GJ Triode Pentode Tube

(1) Tested Westinghouse 6EB8 Tube Date Code 69-22 High Mu Triode Pentode Tube

(1) Tested RCA 6AU8 Tube with Box Date Code KQ Triode Pentode Tube

(1) Tested Sylvania 6KA8 Tube with Box Date Code RAA Triode Pentode Tube

Matched Codes PAIR NOS NIB Syvania USA 6AH9 Tubes Triode-Pentode Tube for Zenith

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

(1) Tested Very Strong GE 6JC8 Tube with Box Date Code CV Triode Pentode Tube