The anode dissipation is 500W with the correct blower, airflow socket and chimney. However if you only cross flow cool them with a cheap axial fan, this reduces to 450W. The loss of 50W for typical SSB use at 600W output is generally considered acceptable. You must cool the seals and must use the anode radiator connector.

Simple spec, 1KW HF, 500W 2metres.

It is always used in grounded grid. The only electrode supply required is the anode. You can ground the cathode to DC and the valve will take about 100mA at 3kV. A low voltage zener can be used to reduce the standing current. Usual value for SSB application is 75mA needing around 8V of bias.

They are a good match to modern 100W rigs on 6m. Naughty on 4m and getting a bit past it by 2m.