Genuine British made Mullard TY4-400 high power (350W dissipation, medium gain - mu 25 ) triode output tube. NOS and show no signs of ever being used. As a transmitter tube good up to 30 MHz. The price is PER TUBE. Limited quantities available. This item is shipped from Britain, in North America or Asia please allow 2 to 3 weeks for delivery.
Here is the spec sheet for this part: http://scottbecker.net/tube/sheets/129/t/TY4-400.pdf