This is a panel mount for the E1171S-DAK3-2020-K01 Incremental encoder with a button. It cannot be mounted in a panel as it has a button inside, so I created this mount/holder so it can be.
The print in the picture is an old iteration, all of the problems (small holes, too loose nut clearance) have been fixed.
Simply insert the encoder into the larger part with the side flaps extended outwards, push it to the top, and secure with the bottom part, 2xM3 hex nuts and 2xM3 screws.
The author marked this model as their own original creation.