Cloth and leather (clothing, sails, trampolines, shoes, boots) often have holes through which to thread lacing or rope.
In many cases these holes are reinforced with a metal or plastic ring to prevent the lacing or rope tearing the underlying cloth or leather.
Some rings are a single piece (like a washer or grommet) sewn to the cloth. In other cases the ring has 2 parts that each go on a side of the cloth and are pressed together to mechanically interlock. For larger rings (e.g. on sails) the 2 halves are sometimes bolted or screwed together.
Is there a proper name or terminology for such rings? For lack of a better word I'm currently calling them grommets, but that doesn't feel right somehow.