Unique vertical solder connections at the top of the tube.
Tube made of high quality SS304 steel with tube tolerance of +/-0.05 mm.
RoHS tin plated brass cap and center pin. Nickel plated brass battery cap.
PEI (Ultem) insulator.
Soldering note: The easiest method to solder the wires is to use pre-tinned wire. Put little flux on the wire and then solder directly with plenty of solder. Thermally there should be no problems, although it is always better to work with more heat and less time than vice versa.