These are BCW Brand standard 20pt. thick 1-Screw Down Card Holders. The BCW 1 Screw Card Holder is made of high impact, crystal clear polystyrene with all of the features and benefits of a 1/4 Inch screwdown in a compact design. This affordable design saves your wallet and your collectible and valuable trading cards! Dimensions - Exterior 2-7/8" x 4"