I've found something like that similar from old Erie Canal lock sites. The disks have a slight bulk towards the middle and were used as washers. Don't know if that's what you have but here's a link to a picture of what I was referring too.
I've found something like that similar from old Erie canal sites. They have the same bulk toward the middle on one side and were used as washers. I don't know if that's what you have but here's a pic of what I'm referring to. View attachment 1832557
The pic is of a more detailed washer but same idea.
Thanks for the responses ya'll. Ya'll nailed it with the identification. The variety of iron implements and their functions you find while detecting never ceases to amaze me. Thanks!