The EL34 is an output pentode introduced in 1953 by Mullard and intended for use in audio amplifiers and modulators . It has an octal base, indirectly heated cathode 6.3V/1.5A, plate dissipation 25W. It's capable to give 11W in Single End configuration and up to 100W in push-pull amplifiers running 800V on plates in B class. Russian equivalent, but not completelly exact is 6P27S / 6П27C

Type	PCS
EL34 EI Yugoslavia (late 80s, early 90s)	150
EL34 Fivre Italy	3
EL34 Philips Metal base	2
EL34 6CA7 Philips Miniwatt - Mullard Xf2 welded plates, black base	4
EL34 Philips XF4	40
EL34 RFT	8
EL34 Siemens (Used in original blue yellow boxes)	6
EL34 6CA7 Telefunken	7