NaturallyMobile voice recorder

I have one of these Naturally Mobile voice recorders, no manuals or
accessories, and am having a difficult time determining what version of
the Dragon NaturallyMobile voice recorder this unit is. It looks like
the pictures I have seen on the web for the voiceit NaturallyMobile
vtr3200, but it has a USB port, and all the NaturallyMobile recorders I
have found on the web all say they have serial ports. On the battery
cover in the back of the recorder, the label says Dragon Systems Inc
Dragon Naturally Mobile Recorder R1, and Model#0532000000. Does anyone
have an idea what version of the NaturallyMobile recorders this is? I
purchased Dragon Naturally Speaking 7 (awaiting shipment), and was
hoping to use this recorder with it, but until I determine what model
this recorder is, I can't even find a manual or user guide for it.