The IEC Thermionic Tube - Triode is a triode amplifier tube (or sometimes called an electron valve or electron tube) that rectifies. A heater inside the tube warms the cathode so electrons can emanate. A DC voltage is applied between the Anode (Plate) and the Cathode and electrons can flow from cathode to anode. A third electrode called the Grid can carry a charge that can control the current flow from cathode to anode. A very small amount of power at the grid can control a much greater amount of power through the tube. This is the function of a amplifier.
4mm spin free IEC terminals are provided for all connections.

Instruction Sheet