Ours came with stud & clamp things which held the chairs secure. Linda took off the clamps & slipped the D ring of dog collar over stud & tightened the wing nut. Then the collar was put around the base ring which allows a bit of movement, ?10inches or so?, and we unsnap the collar when we want to really move a lot. I have not yet had the chairs move enough to need the restraint the collar offers. Oh, the collar is a nylon web collar with those plastic snap together clippy doo widgets.
As we had the first Euro chairs installed, the stud mounts in floor may not be what you have.
kevin