This is the Langstroth and The UD Intrance (entrance on the inside)
This innovation came about when we questioned the logic of Langstroth’s 1852 patented bottom entrance. Having read his 330 page book it became clear that while it was part of his revolutionary patent for the removable frames, there was little if any research done by him on the suitability of an entrance at the bottom of the hive.
You can have the hives custom made for you using this design or you have a choice of purchasing a set with a 25mm saw tooth forstner bit if for the Closures to fit properly. Then you can do the Intrances on the hive.