These were on a T rear spring I got. They are not cut down shocks they are fully forged with no cutting done. There is a K or R in a triangle and the No2 on each that I have found so far. They may have been off some car from the teens or 20's and were used on a trailer but I don't know. The spring eye holes are correct size for T, the other is larger but my be missing bushings.
They look like some early endless chain links from farm equipment.
I believe those are parts from a speedster/racecar lowering set up. The way I remember it, the rear spring perch gets inverted, a rod goes thru it and forward, this shackle goes on that part of the rod, the forward end of the rod is bent 90 degrees & flattened and bolted to the radius rod. A second cross member is installed in front of the original rear cross member, and the spring sits in front of the rear end, in the second cross member