National Underfloor Entrance - Top Bee Space with Varroa Mesh

For National hives using top bee space.  This includes the very popular Abelo 12 frame Nationals that we use here at Broads Bee and many more.  This version has a full size varroa mesh and the option to add a varroa inspection board.  We don't use the boards here, we check our varroa loads with an alcohol wash so we thought that we'd offer the option to not include a board.  The board is made from a thick correx sheet and should only be inserted when actively checking varroa counts.