Russian tube 6J4-V (6Ж4-В) is an sharp-cutoff high transconductance pentode of increased reliability and mechanical strength, intended for service as a wide-band video or radio frequency amplifier. It is also suitable for use as a mixer or oscillator. It is direct replacement for the american 6AC7 (1852) tube and also for the 6F10 from Tesla. You can also use it instead of the chinese 6J4P (which has another shape, bulb type). New old stock tubes, directly from the factory packing. Made in the 80's (please see the gallery).