6C4P 6ц4п ~ EZ90 / 6Z31 Tube Dual Channel kenotron Rectifier Soviet USSR Reflector NEW 2pcs. New black plate 4 x 6C4P = 6Z4 ~ 6Z31~6X4 Rectifier Reflector tube late 60`s. The 6C4P (6U4P) double kenotron with a common cathode has been designed for use as a low-power rectifier.Cathode: indirectly heated, oxide-coated.
eBay