A card sleeve for board games is a protective cover that is used to encase and preserve trading cards or game cards. These card protectors are typically made from a transparent, durable plastic material and are available in various sizes to fit different types of cards. They serve to extend the lifespan of the cards by preventing wear and tear from frequent handling, as well as reducing the risk of damage from spills or other accidents. Additionally, card sleeves make shuffling easier and more smooth, enhancing the overall gaming experience.