The vent covers are plastic covers that are installed over vents to block airflow entirely, commonly used to prevent drafts, improve insulation, or block unused vents. These covers help save energy by sealing off areas where heated or cooled air might escape, contributing to energy efficiency and cost savings under the VEU program. It provides a quick solution, If you put them on no cold air will get into the house, no spiders and no heat will escape from house and it will keep the house warm.