The Harvest Lane Honey Beehive Entrance Reducer fits 10-frame Langstroth beehives and seamlessly integrates with HLH bottom boards. It features small and medium gaps and can be used to completely close off your hive. It's used to reduce the entrance of a hive during new package introduction and to prevent the hive from housing too much cold air during winter. It also works well for closing off the hive for transport, or during area pesticide spraying.