The BCW Golden Age Backer Boards are made from 24-point solid bleached sulfate, coated and buffered on one side with 3% calcium carbonate, and are precision cut to size. Use this item to protect and store your collectible golden comics. Certified Acid Free – Independent Lab Tested. Use with BCW Golden Poly & Mylar Bags. 100 boards per pack. Dimensions: 7 1/2″ X 10 1/2″.