Air-Cooled Hot Cathode
- Westinghouse WL-341 Coolidge Tube
- “Victor” Early Coolidge Tube
- “TUBIX” Line Focus Tube
- Spherical Hooded Anode Coolidge Tube
- Siemens-Reiniger-Veifa Coolidge Type Therapy Tube
- “Okco” Hot Cathode Tube
- “MEDIA” Line Focus Tube by C.H.F.Müller
- AEG Coolidge Therapy Tube
- “4UD” Therapy Tube by General Electric