Blind chain connector/coupling replacement

First upload, yay!

Simple one-piece replacement coupling for a ball chain used in roller blinds (for example older Jysk blinds). Designed for ball diameter of ~4.5mm.

The original part had a living hinge which gave up and the part split in two. The other half of the part vanished and probably got eaten by a vacuum cleaner so I decided to make a better one with no living and especially no dead hinges but just one piece with a satisfying snap. :) Minimalistic and robust design with nice round shapes and max 45 degree overhangs for easy printing. Definitely does not look like the original one but can still be considered as Scandinavian design (made in Finland).

Print/assembly instructions:

The model should print easily and quickly with 0.1-0.2mm layer height, no supports/post-processing needed. Recommended to print with PETG as it flexes a bit more than PLA. The balls are easiest to snap in place with pliers but I was also able to do it with my fingers only. The fit should be fairly tight but the balls should still move when in place. Mine has been in use for a while now and it holds really well and does not come loose with normal pulling force during use. Depending on your printer, you may need to scale the model up/down a few % to get the perfect fit. Editable FreeCAD file also included if you want to customize more.

If you print it, please share your experiences so I can do some tweaks if needed!