This process typically produces a near net shape workpiece, which means the final product is almost finished although it can sometimes create the final product less plating or heat treating.
An important consideration in heading is the tendency for the wire to buckle if its unsupported length to diameter ratio is too high.
There are a variety of cold heading machines but typically for fastener manufacturing you will see one die two blow up to five die six blow and beyond.
Multi-die headers allow for more complex parts to be formed as part of one process due to the above limitations of diameter ratio reductions.
Also, because the part is formed rather than cut, the grain flow stays intact and creates a much stronger part for its size.