It is a camera holder part for Ender3s1. The design was made according to the table parking position seen in the photographs. The camera is a Creative brand 1080P Live camera. The camera has a 360 degree spherical adjustment mechanism and there is a slot on the FDM part for up and down adjustment.
I recommend that the slot on the movable z-axis to which the part is connected be made precisely, and therefore you adjust the measurements in the CAD data according to the tolerance values ​​of your own 3D printer.