UTI type for .p12, .pfx

For being able to pick client certificates, I thought I can simply create my own UTI for certain extensions and feed that to UIDocumentPickerViewController(documentTypes:) to change the way it displays files.

This works for fantasy extensions and .cert, for example, but not .p12 or .pfx. Which may be because these are already used in other UTIs. But this list of UTIs doesn't contain them.

Is there an existing UTI for certificates that I could use?
UTI type for .p12, .pfx
 
 
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