This is a reverse engineered bushing for a SteppIR antenna. SteppIR calls it a Sweep Diverter. Because the thickness of the paint over the fiberglass rods can be inconsistent the printer is encouraged to print one and dry fit it. I had to print mine at 100.5% in X and Y and 100% in Z for a snug but not too tight fit. As always YMMV. I printed mine in PETG with 40% gyroid infill, 0.4mm nozzle, 0.2mm layer height.