The file 'Ring Holder For Single Or Three Rings 3D Printer Model' is (stl) file type, size is 108.2KB.
Pretty simple print, should not need support. You can scale it a bit as needed to keep it proportional to your rings. Ladies rings may look better with this scaled down.
Two walls and 25% or less infill should get you going.
Update- I also added a simple single ring holder.
3ringholder2.stl | 293.1KB | |
ringholder1_fixed.stl | 60.1KB |