This 10 frame inner cover is meant to last with a heavy 3/8" plywood core and extra wide pine rim.
One side with an upper entrance notch has a 3/8" space while the other side has a 1/4" space between the rim edge and the plywood face.
An inner cover is an easy way to provide an upper entrance and prevent bees from propolizing the outer cover.
A beehive inner cover allows moisture to escape and fresh air to be circulated throughout the hive, and acts as an upper entrance/exit when properly used with an outer cover. After your inner cover is on with the notch forward, add an outer cover and make sure the outer cover is pushed forward so there's a gap at the front of the outer cover. This allows air and bees to go through the notch in the inner cover, all year round.
During winter, turn the notch side of the inner cover down to provide an upper entrance and ventilation. This also means the deep side of the rim is downward. In the summer, turn the notch side up. This also will make it so the shallower side of the rim is down, ensuring the bees have no more room above the frames than the normal Bee Space. If the deep side is down in summer, bees will build a lot of comb just under the inner cover.
Comes fully assembled.