how to Locate or Set coordinate system to circular parts

[muks]

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as well as seal (the black ring).

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Do you mean you want to measure the diametre covering the holes? Presence/absence?

[PKC]

Only absence presence of seal.

Thanks,

Praveen

[muks]

I am not getting what you mean by the seal

[PKC]

Attached image means seal missing.

Thanks,

Praveen

[muks]

It should be pretty simple given that there is no measurement involved.