> 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/use-cases/editing-line-segment-properties-pid/inserting-symbols-pid/understanding-assigning-pipe-spec-data-pid/changing-key-property-in-symbol-pid.md).

# Changing Key Property in Symbol (P\&ID)

This chapter describes how changing the Key property triggers the assigning of pipe spec data.

Typically you would set the Key values in Project Setup (see [PSD\_Key Suggestion](/plant-tools/plantspecdriven/how-to-use/configuration/pid-classes-symbols/psd-key-suggestion.md)).

If you insert a check valve you can see the Key value. Based on this property and the size PlantSpecDriven filters the pipe spec for suitable parts.

![](https://2994090777-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FZH2AGHzvPfBW7YdaaGc0%2Fuploads%2Fgit-blob-515b2ee37489b68ba7aa995ac289ab959bf5db2f%2FUse-Cases-0151.png?alt=media)

If you insert a ball valve you will see a different Key.

![](https://2994090777-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FZH2AGHzvPfBW7YdaaGc0%2Fuploads%2Fgit-blob-e83d16f935b45ef2a01c3bf7542525caa1956f47%2FUse-Cases-0152.png?alt=media)

If you insert a general valve symbol you see that the Key shows just **V-**. The Key behaves like a wildcard. In this case the Part Selection dialog shows all parts which start with V-.

![](https://2994090777-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FZH2AGHzvPfBW7YdaaGc0%2Fuploads%2Fgit-blob-530c8ab316f5f7347781250c4cec9e0b03cd60f6%2FUse-Cases-0153.png?alt=media)

If you overwrite the Key for example with **V-Globe** ...

![](https://2994090777-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FZH2AGHzvPfBW7YdaaGc0%2Fuploads%2Fgit-blob-fb846366010276cdeb380639235c7cbab3e9c90c%2FUse-Cases-0154.png?alt=media)

...the Part Selection dialog will show only the globe valves.

![](https://2994090777-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FZH2AGHzvPfBW7YdaaGc0%2Fuploads%2Fgit-blob-aaba9ac237ddde8caf7d4946fe65fda79100a03c%2FUse-Cases-0155.png?alt=media)

As always, after selecting a part of the dialog you see the assigned data.

![](https://2994090777-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FZH2AGHzvPfBW7YdaaGc0%2Fuploads%2Fgit-blob-feeaa4abfa375ea7b8ea8de24b5df96dcb47200e%2FUse-Cases-0156.png?alt=media)

You can also enter multiple Keys separated by a comma.

![](https://2994090777-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FZH2AGHzvPfBW7YdaaGc0%2Fuploads%2Fgit-blob-e44846ec4f5f7667ff335437474c62a9d22a1121%2FUse-Cases-0157.png?alt=media)

Now you see the ball and globe valve parts.

![](https://2994090777-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FZH2AGHzvPfBW7YdaaGc0%2Fuploads%2Fgit-blob-03072022056e3560b87be15d22e3e1d6ea609d20%2FUse-Cases-0158.png?alt=media)

If you type in **V-Check**...

![](https://2994090777-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FZH2AGHzvPfBW7YdaaGc0%2Fuploads%2Fgit-blob-39ca41633835f3098f406f84be2a784814342e77%2FUse-Cases-0159.png?alt=media)

...no Part Selection dialog will appear, because there is just one check valve in the pipe spec for size 100.

![](https://2994090777-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FZH2AGHzvPfBW7YdaaGc0%2Fuploads%2Fgit-blob-e4a30d44c59c0f657f0d2ae3fb1faccfd159aa95%2FUse-Cases-0160.png?alt=media)