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• Most websites I ran across seem to say plexiglass... but note there may be some bias as these also tend to be websites that sell online and delivery of plexiglass is easier,
  • Hollywood Poster Frames is for plexiglass
  • https://www.postercollector.co.uk/how-to-guides/how-to-frame-movie-posters/
• My local framer The Art Forum recommended glass (he has both) as he feels plexiglass yellows over time - heTony's been in the business a long, long, time  , so I went with Anti-UV, Anti Glare, extra clear glass.

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• http://hollywoodposterframes.com/ - pre-built frames,
• http://www.spotlightdisplays.com/ - Flip frames (not sure what that means),
• www.displays2go.ca - search for snap frames (also has lightbox models) - not sure if archival though

Putting it Together

Here are things to check with your framer,

• Back the linen poster with acid free material
• Acid free foam core or 4 ply rag are best
• Linen Hinged - Hinge mount using some archival tap stuck to the linen
• Do not stretch
• Trim the linen about 1/8 smaller than the inside dimension of the frame
• If framing with wood make sure to put a barrier if framing to size

Hanging

As these posters are quite large it is very important to hang them properly to not buckle over time,

• Use the D-Rings on the back directly
• Warning - Adding wires to D-Rings for Large posters will put strain on the frame causing corners to pop out.

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