The inner cover sits just below the outer cover and above the top box — think of it as the ceiling of the hive. Without one, bees glue the outer cover directly to the top frames with propolis, and you'll be prying it loose with a hive tool every time you open the hive. What You Get Creates an air gap between the top box and the outer cover, cutting down on condensation buildup in winter Center notch or hole doubles as an upper entrance or ventilation point, and gives you a spot to add a feeder Keeps bees from gluing the outer cover directly to your frames with propolis Fits standard 10-frame Langstroth equipment Seasonal Use Leave it on year-round. In winter, the air gap it creates helps manage moisture inside the hive — trapped condensation dripping onto the cluster is a bigger winter threat to bees than cold on its own. Product Details Fits 10-Frame Langstroth Material Wood You May Also Need 10-Frame Cypress Metal Capped Telescoping Cover 10-Frame Cypress Screened Bottom Board 10 Frame Wooden Entrance Reducer