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- Total extent in linear feet
- Extent of photographic material
- Extent of audio/visual material
- Extent of born-digital material
If there is easily measurable material, of significant amount (over 10 items) it should be split-out and recorded in its own 300 field.
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300 $$3 Includes CD-Rs: $$a8 items $$a (5400 MB5.6 GB)
300 $$3 Includes floppy disks: $$a2 items $$a (20.8 MB00288 GB)
$$b Other physical details. If the material is not easily measurable (such as single photographs scattered throughout correspondence files), but is definitely worth mentioning [i.e. over 10 items], then mention the format word within the inclusive 300 field in a subfield $$b and use the word “uncounted”
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