Updated. Ran into a cubical style that a narrower slot and someone wanted a hook instead of ring, so added those two items.

Wanted to add a chain that could be strung across our cubical entry, so needed a ring that could hook into our cubical wall sections. Not sure on the brand of our cubical walls or how interchangeable cubical wall mount systems are, but these worked for ours. I've attached a link to the Fusion 360 models so you can modify them if needed.

Flat Ring: https://a360.co/2OmZ4DH
Right Angle Ring: https://a360.co/2QzJcPV

Prusa

i3 MK3

No

Yes

.2mm

20%

The straight fitting doesn't need supports to print as long as you print it with the ring flat on the build plate. The right angle one is best printed with the ring flat against the build plate and use supports since the tines that hook into the cubical wall will need them.

You may need to mirror them depending on which way you want them pointing.

2 perimeters and 20% rectilinear infill in PLA seemed to be strong enough for my application, but you could add some perimeters, increase the infill density, and/or use a stronger material if needed.

I needed to trim the slight brim that developed at the plate. It's a pretty tight fit into the cubical wall mounting slots. If you don't trim off the bit of squish at the plate, it may not fit. Your print may be different in this respect