The BCW 3x4 top loading thick card holders are designed to hold cards that are thicker than standard Trading cards. Here's an easy way to gauge the thickness of a memorabilia card-- a regular card is about 20-pts. Thick. Thus, you can stackup regular cards next to the memorabilia card and do some easy math. That is, If your memorabilia card is about the thickness of 5 regular cards, then it would need a 100-pt. Holder. BCW 3x4 top loading card holders are made of high-quality, rigid PVC. These top loading holders are some of the most popular rigid individual card holders in the collectible card industry. Use this product to protect, store or display yourcollectible cards.