For getting rid of the heat of the CPU the Streacom FC5 uses a system of multiples heatpipes, that go from the CPU socket to the right side of the chassis. There are screw holes in various places, and the mounting system is constructed in a way that allows for some flexibility when you are installing the components. That is what makes it possible to fit different motherboards, not just one specific model. We mentioned the spacial limitations already, there needs to be an open path between the CPU socket and the right side.
The CPU socket also can't be located too far from the typical spots, as the leeway you have with the heatpipes is limited. It will become clearer on the next page, when we walk you through a complete installation. Below you can see the included heatpipes and other parts you receive with the Streacom FC5.