Lavalier transmitter for the lapel mics. Trump had one too. When I use my wireless for my guitar, I have a similar sized transmitter on my belt or hanging off my pocket.
Were they wearing lapel mikes? I thought they were on lectern mikes. Where were the mikes attached?
I didn’t see any lapel mics on either Clinton or Trump...The only mics I saw were on their podiums...
I thought the lecterns had mics.