TUBES Preamp Grade SWGP (# 292083306570 ). 6N23P / 6H23N / 6922. Voskhod 6N23P Silver Shield SWGP. Choose Wisely with VOSKHOD "Space-craft" 6N23P (6H23N in Cyrillic), and not the other versions. 6N23P, 6N23P-EV (6H23n, 6H23n-EB).
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