Unused rack openings shall have blanking panels installed to reduce bypass airflow through open spaces in racks and cabinets. Panels shall be designed of non-metallic material with a snap-in feature that allows easy installation by hand. A latch design will allow for installation in round tapped holes or in square holes with or without cage nuts. Panels shall seal properly between rack units to prevent bypass air. Panels shall enable the blanking of multiple rack unit configurations. Panels shall be designed to stack easily to minimize storage space while products are not being used.