100 E. Gerber Mylites 2 Mil Mylar Silver Gold Comic Book Sleeves 775M2 Protection from Humidity Protection from Volatile poly bag breakdown Protection from Acid migration Protection from Oxygen decomposition Protection from Insects 100 E. Gerber Full Back SILVER GOLD SIZE 24pt Acid Free Backing Boards 750HB These are the highest quality boards found anywhere! At 24-Mil, these provide greater protection than regular backing boards! Made from 100% acid-free, virgin wood, cellular fiber, 24 mil. thick cardboard. Contains a 3% alkaline buffer and a pH content of 8.0-8.5. Sold in packs of 100; Measures 7 1/2" x 10 1/2". White on one side and cream on other