You do want “No plug”, and you’ll need to wire it to a suitable plug, or you can of course (and probably better and more reliable) make a permanent connection, but I understand you’ll need a registered electrician for this. Do you want to monitor the voltage on both legs of your split-phase supply? If so, contact ‘The Shop’ and ask, because you’ll want a special ‘two-input’ version, alternatively the 3-phase version with only two inputs used.
See also emonTx V4, emonVS in North America