I have not been able to solve this puzzle. I believe that the objective is to remove the larger circular ring, not the 2 smaller ones.
This is a Horseshoe and Ring puzzle, personalized for someone with initials S.I.G..
I found this visual solution for it, which I think explains the solution clearer than a video.
First notice that the ring is not actually linked into the horseshoes - so it is on the outside, and so we are trying to transform the horseshoes into a shape that makes this relation more obvious.
If you look at step 4. the trick to see if that the ring can be removed over horseshoe 34 due to the slack in the chain between ends 1 and 3 (move the part of the ring closest to the camera at 4 along the ring to 3).
Now you can use the same trick to remove the ring from your puzzle.