Count your weep holes and order the number of packages you require. Clean out weep hole of debris. If excess mortar exists inside the weep hole from the brick layer (small % of homes have this) may have to remove with mason drill or chisel in order to allow for installation of cover. Removal of excess mortar (trash mortar) is good for wall ventilation. Cover size is 2.75 inches tall, Can be cut or stacked to fill different height weep holes. Pinch to insert, wear work gloves and eye protection when cutting. Excellent for maintaining wall ventilation, openings large enough to avoid clogging with debris over time. Stops mice, wasps, lizards etc while allowing necessary moisture out and air in.