What's more the tube can be refilled co2 gas some times if the inner co2 gas use up.
Optional tube:
1, Synrad 60W air cooling
2, Synrad 100W water cooling
3. Coherent 100W water cooling
4. Synrad 150W 200W 250W 400W
The price in this page is for Synrad 60W air cooling RF tube.