Digital BW, The Print

Hi Arthur -
You really don't need a commercial product to accomplish this. My method has been to cut  four strips of 
archival mat board to the width that the frame reaches into cover the print, or slightly narrower. Then you
can use a board the exact size if the print paper, behind it, the strips on top of the four sides, and the glass
on top of the that sandwich. The strips will be hidden under the frame, and the glass spaced above.

The complication can come, especially with glossy paper, if the print doesn't lie flat. Since most of us no
longer will dry mount prints, sometimes a slight curl will flatten out with the most minute amount of damp
sponge on the back of the print. I'm talking about the sponge being practically dry, and it should be laid on the 
entire back of the print, not just in sections.

Hope this helps,

Clay Price