Terminators, also known as loads or dummy loads, are used to dissipate RF energy without radiating electromagnetically. They are used to cap-off unused ports on couplers and dividers, maintaining the device’s impedance and VSWR specification.

The load value, in this case 1 Watt, defines the maximum amount of energy capable of being dissipated. RF energy is dissipated through thermal radiation, i.e., heat, and consequently large loads require heat-sink features.