So, most older security radios, including the ones I've worked with, have attachments you can put on them such as lapel mics/parrots or sleeve/earpiece attachments. They still require the base unit to function. What I'm trying to sell here is that there is the base unit on his waist and he's got it hooked up to a sleeve mic. Unfortunately, Ai Shoujo doesn't have any really good cord attachments (or didn't at the time) so I didn't bother trying to show the attached "cord." You'll find I did the same with Galka and selling the illusion of a parrot/lapel mic.
Good eye for detail, though!