Michael and Vaughan in “Unfinished Business”

So how do we know it's not Lester's?

Leeches don't use phones.

How come?

Look, the only machine that can see or hear a leech is us. You can only see them face to face. No mirrors, no photos, no videos. Audio's the same. He can make a call, but his voice won't go down the line. Surveillance is a bitch.