I'm not 100% sure of anything other than I've had normal conversations on mine with no complaints.
I can her the other party talking even as I am, which would suggest full duplex.
Buy from Amazon or Walmart or target and return it if it doesn't fit your needs.
It's not a problem on a phone because the speaker doesn't feedback into the mic, but that's not the case with a speakerphone. So the latter generally shuts the speaker off when the mic is activated and vice-versa. You think you're talking at the same time, but the other party is not actually hearing you.
I didn't know about full duplex on speakerphones until I read about it in reviews....it appears it's mostly only high-end speakerphones that have it.
