NanoPi-NEO Heat Sink
Custom Heat Sink. With the processor on the "bottom" of the PCB, the NanoPi NEO can be mounted with a heat transfer foam pad between the processor and the wall of any metal enclosure. Otherwise, you will want the NanoPi NEO Heat Sink.
The NanoPi NEO is very small and needs some help in getting rid of heat. This official custom heat sink will do the job. Includes thermal pad (not paste).