Looking for some help with Colt style firing pins

[MinerJohn]

Hey folks, I have these two firing pins. The pin on the right I'm pretty sure is the J frame lawman type. The pin on the left is the one I cannot seem to identify. It has the much thinner rim. Does anyone have an idea of what that pin may be for?

316593, 316594, 316595

[Forrest r]

left: colt trooper
right: colt trooper mk III

[hiram]

https://www.gunpartscorp.com/gun-manufacturer/colt/revolvers-colt/trooper

https://www.gunpartscorp.com/gun-manufacturer/colt/revolvers-colt/trooper-mkiii

https://www.gunpartscorp.com/gun-manufacturer/colt/revolvers-colt/trooper-mkv