Here in the Pacific Northwest, condensation is a sure-fire way to make your bees unhealthy. It’s already soggy outside. The last thing your bees need is a drench of frigid condensation raining down from the inner cover. Even in winter, your bees need plenty of ventilation. And in the summer, ventilation helps to moderate hive temperatures and facilitates the honey curing process. Ventilation may even help to minimize Nosema. Second, screened IPM (integrated pest management) bottom boards assist in the management of Varroa mites, which are a principle cause of colony failure. Ours accommodates a mite board (sold separately). Extremely strong and durable, with glued joints and galvanized metal screws. Built to last. Made in Corvallis.