At auction:

Exceptional nickel-plated art deco carbon microphone from the 1920s-30s era by General Sound Equipment. Looking straight out of a Frank Capra movie, its classic styling consists of a center carbon microphone (stamped “General Sound Equipment”) suspended by eight springs within a large nickel-plated ring atop a vertically ribbed shaft. Stamp on base reads: “Pat in USA, Aug 16 04, Sept 13 04, Jan 26 15, Western Electric Company”. SIZE: 19-1/2” h (including contemporary replaced NBC lightning bolt marquee).
Visually near excellent, untested, affixed with replacement cloth-covered cord. Exceptional for display.

You can find the piece here: RCA microphone auction.