This video is a summary of the manufacturer parts markings that I found on my 2018 model, 2022 production Colt LE6920SOCOM.
Added: I forgot to show the buffer in the video. It is marked H2.
The Colt AR-15 Resource
"A site dedicated to the history of the Colt AR-15 rifles, carbines and associated items"
The Colt AR-15 Resource 