YOU ARE BIDDING ON A VINTAGE TUNG SOL 5881 JAN CTL 6L6WGB. THIS TUBE TESTED GOOD ON MY B&K MODEL 700 DYNAMIC MUTUAL CONDUCTANCE TUBE TESTER AS SHOWN. PLEASE LOOK AT ALL PHOTOS AND ASK ANY QUESTIONS YOU MAY HAVE. REMEMBER THAT I SELL MOSTLY ANTIQUE AND VINTAGE ITEMS AND THAT THEY ARE MOSTLY LIKELY NOT BE PERFECT DO TO THE NATURE OF THEIR AGE. IF YOU HAVE A PROBLEM PLEASE CONTACT ME BEFORE LEAVING FEEDBACK.