This 10-Frame Inner Cover by Betterbee enhances hive ventilation and reduces moisture, a year-round essential. It features a notched rim for adjustable airflow, allowing for an upper entrance or exit for bees. Constructed from durable masonite with a white pine rim, it is designed to prevent propolizing of the outer cover. In winter, the notched side faces down for ventilation; in summer, it faces up to maintain ideal bee space. Fully assembled, it measures 16-1/4" x 19-7/8", providing a functional, lasting addition to your hive setup.