I do not have the SDC2160 in my possession yet. However, as I was preparing a drawing for mounting the controller, I looked at the mechanical drawing at the end of the datasheet and saw the mounting holes labelled as "R3.6" (Diameter=7.2mm) That seemed like a very large hole for such a small device, requiring an M6 screw. I downloaded the step model and opened in my CAD tool and found that the mounting holes are a diameter of 3.2mm in the upper case and 3.5mm in the base plate. That seems more appropriate and correct dimensions for an M3 screw. FYI.