TAD Bias Master BM4 Meßgerät für Bias
TAD Bias Master BM4, Measuring Device For Bias, Four octal socket adapters, For the control of the retirement, At 6L6GC, 6550, EL34, 6V6 GT, 5881, KT88, KT66, KT90, KT100, 7027A, With illuminated display, Made in Germany