> For the complete documentation index, see [llms.txt](https://help.auxalia.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.auxalia.com/plant-tools/plantspecdriven/how-to-use/configuration/pid-properties/fasteners-class.md).

# Fasteners Class

As mentioned under [AutoPipe](/plant-tools/plantspecdriven/how-to-use/concepts/autopipe.md) PlantSpecDriven can add Fastener objects (e.g. Gaskets) to your P\&ID symbols. These Fastener objects will not be visible in the drawing, but they are stored as NPOs (Not-Placed Objects) in the P\&ID database.

If you don't need Fasteners you can skip over this section. You typically create the Fasteners class under Piping Fittings. You will later see which additional sub-classes you may need. This will be explained in [P\&ID Classes & Symbols](/plant-tools/plantspecdriven/how-to-use/configuration/pid-classes-symbols.md).

### <mark style="color:blue;">PSD\_OwnerPortNumber (mandatory when using Fastener with AutoPipe)</mark>

![](/files/jqFlOu7bxUevwuR3a4aD)