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- acid-free
- acid-neutral
- avoid foamcore unless acid free such as Artcare Archival System by Bainbridge which should only be a few dollars more
Linen Backing,
- Expensive and fixes flatten and hide vintage folded posters.
- Make sure to go with professional who will make it reversable
- For vintage folders will bring up value if resold
- ~ cost $75 to $150
- Not advisable for double sided posters
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