... rods: pothook spring cathodes for electron tubes, cathode gas discharge lamp houses, etc.4) Tungsten-cerium rods: ... for electron tubes, cathode gas discharge lamp houses, etc. 5) Tungsten-lanthanum rods: electron tube cathodes, transmitting rods, ... temperature resistant molybdenum foil6) Tungsten-zirconium rods: electron tube cathodes, transmitting rods, heaters, high temperature resistant molybdenum ...