There is no way that you can tell other than by comparing the layout of the
labels (number across, number down, dimensions etc) with the details of the
labels that are available under the Label Options dialog or by looking on an
Avery website where you can probably find details of the labels.

Signature
Please respond to the Newsgroup for the benefit of others who may be
interested. Questions sent directly to me will only be answered on a paid
consulting basis.
Hope this helps,
Doug Robbins - Word MVP
> How do I know what type of labels were used when creating
> a new document of labels (after the document is saved).