You spin me right round...
Silverstone are one of these clever manufacturers who realise the key things with anything that spins is noise, so to help dampen your cooling fan of choice, they include some silicone washers to make your life a little quieter.
Once the fan is mounted you can see there is only a few millimetres of clearance between the base heatsink and the fan hub, but that's all we need!
The HS/F has to be securely fastened to the motherboard, so a backing plate is used instead of the flimsy plastic push clips on some heat sinks (I always end up breaking them).
This is starting to look vaguely reminiscent of installing a block for a water-cooling system.
The base of the heatsink allows you to attach brackets for different mounting options, including AMD flavours.