"Drive-ing" me crazy (haha get it!)

[Ronald Ziehm]

Please help me figure out what in the blue blazes this thing is and what I do with it. I find it nowhere online, nor inside of manual, official GMC, or otherwise. It driving me up the wall trying to surmise it's name and/or use

 

[Jimmyy]

Looks like a microphone.

 

[iamdub]

Please help me figure out what in the blue blazes this thing is and what I do with it. I find it nowhere online, nor inside of manual, official GMC, or otherwise. It driving me up the wall trying to surmise it's name and/or use

View attachment 267757

Old school GM OnStar microphone. Part #15247279