Easy Bolts allows you to place Bolts in four different ways.
The first method is an automated placement of bolts from the content center as standard. If selected, the nut and washers are constrained to the bolt.
The second method is also an automated placement from the content center but the bolts are stored locally as custom parts.
The third method is a little unusual and serves mainly to keep the file size and complexity of the model down. It uses an assembly file with one dummy part file which mimics the volume of the bolted joint. The assembly also contains all the parts of the bolted joint as virtual parts. The parts lists from the drawings will correctly indicate the parts and numbers, although in the model there is only a dummy visible.
The fourth method creates normal Autodesk® Inventor® parts and stores them locally. There is no connection to the content center.