10 PACKS OF 100 PER CASE. The BCW Silver Comic Bags are an acid free, archival quality product made of crystal clear polypropylene. Use this item to protect and store your collectible silver comics. Available in 2 sizes so you can now fit your thickest silver comics into the appropriate bag. - for your silver comic needs - 2 mil material thickness - 1 1/2 inch flap for closure - Crystal clear - Protect comics while handling - Use with BCW Silver Backing Boards