This is a bracket to mount an external antenna when using external RF module. In addition to printing this, you need M3 screw, nut and a short SMA cable.
The bracket is designed to sit in the location where the pictures show it mounted. To mount it on the other side, mirror the part.
Print rotated 180 degrees in X or Y axis, the chamfers should be on the print bed to reduce or eliminate cleanup after print.
The part I used to add a connector for internal RF module antenna: