You can see the original synchronizer contact for controlling the flash, and right underneath is an opening we made for connecting the electromagnet to operate the shutter. The Compur shutter is now neatly sandwiched between the 2 turned aluminum rings that are attached to the Nikon flanges. By drilling small holes of 1.5 mm, we are able to use the original screws. Here and there are small openings left over from the removal of extraneous parts, but we will go back later to close these up so that no bits of dust get into the shutter. Once the Compur shutter is mounted onto the camera and the shutter is closed, then the camera is protected from direct dust particles. The new shutter is attached just like an adaptor ring.