The VTC-6264D4 from Communications & Power Industries is a Traveling Wave Tube with Frequency 5.85 to 7.1 GHz, Power 400 W, Gain 49 dB, Collector Voltage 49% of Ew to 55% of Ew kV (DC), Cathode Current 290 to 310 mA(DC). Tags: Helix. More details for VTC-6264D4 can be seen below.