The cover is made to set a 5 frame deep frame nuc over 2 ten frame
deep supers. When the entrance to the hive at the top is closed off
and the bottom entrance opened below, the same amount of bees flying
out that would be spread over a 10 frame super are compacted onto 5
frames which is very good for queen rearing. Another advantage is that
it is easier to lift off the 5 frame super when looking for brood to
move up above the cloake board.