In All This and Gargantua-2, Billy mentions to Rusty that Hank gave him one of the watches as well which he had been told was a gift from Rusty but Rusty points out he had no idea, implying it was just an old watch he no longer needed.
In The Diving Bell Vs. The Butter-Glider, Brock finds out Hatred has his old communicator watch after he had shipped it back to Rusty from Argentina via a Mailboxes, Etc.
Hatred: I'm tired of you always "brock-blocking" me, Samson! I'm head of security! I'm the new sheriff of Venture Town! I wear the watch now!
Brock: That's my band. That's my watch band.