Pack of 50 E. Gerber Premium Large Oversize Comic Book / Magazine / Letter Full Back Archival Acid Free Backer Boards.

Dimensions : 8-1/4" x 10 1/2"

E. Gerber Premium Full Backs are made of 100% acid-free, 42 mil thick cardboard.
Use inside poly bags or mylar bags (sold separately) to safely protect the spine of your comic book and help prevent bending and other damage.
E. Gerber Backer Boards are matte on both sides, as as the 3% alkaline buffer is in the entire board and not just on one side or the other.

What makes E. Gerber boards better?
Most standard SBS type backer boards - such as BCW, ComiCare, and other leading brands - have the acid-neutralizing alkaline buffer on one side of the board.
That's why they're shiny on one side and matte on the other.
When used properly those boards are OK for short term use but really should be replaced every 5 years or so as the acid free qualities of the board can change over time.

E. Gerber Premium Backer Boards have the 3% alkaline buffer mixed throughout the board making them retain their acid free, archival state much, much longer.
E. Gerber Boards meet strict US government standards for archival storage.