Yes, the lateral reach of the light booms (Standard or Compact) can be extended by adding the interchangeable extensions. Simply unscrew the black plastic handle at the front plate of the boom, and slide the extension off. You can choose from 24, 30, and 48″ extensions all of which are compatible.
It is important to consider the maximum payload, as adding an extension decreases the capable payload of the light boom (think of it as sliding further back on a see-saw).
You may have to adjust the rear counterweight placement with the added extension (though this is easy thanks to the tool-free design of the light boom).