Question: One confusing scene

I didn't understand something in one scene.

In the scene where Kevin Costner was being transported in the car, right before he kills the agents and escapes:

Costner looks at the agent sitting in the front seat, and the camera focuses on some mechanical device in the agent's hands, as if he's assembling it, or preparing it, or something like that. My question is what was the device the agent holding in his hands? I didn't get a good look at it.

While watching, my first thought was it that they were corrupt agents preparing a hidden weapon to kill Costner to silence him, which would have been interesting, but then that's not where the story went.

Anyway, later when Costner kills the agents and escapes, I thought for sure Costner was going to pick up that device, whatever it was, since the camera had focused on it, so it was probably important, but then as it turns out, as far as I noticed, it never showed up again in the movie, so I still wonder what that was.

Anyone know what I'm talking about?