This is a handy accessory for starting new colonies. Since bees build up better in smaller spaces, this allows you to limit the working space in the hive by blocking off part of the hive while the bees build up. Please note: this leaves a gap at the bottom, so it doesn't completely close up the space and can't be used in a two-queen situation.
Fits great! Good snug fit, perfect for divided colonies!
Fit great in a couple different 10 manufacturers boxes. They do hang below a standard deep box so they could be used as a divider for running multiple colonies in a single sized box which is what I'm using this for.