Bumble-bee castle access tube
The access tube provides wax moth protection for the bumblebees. The wax moths adhering to the bumble bee's body can be stripped off when entering the bumble bee castle.
Until a few years ago, the bumblebee castle was delivered without an access tube. It can be reordered free of charge, only shipping costs are incurred.
The tube is inserted into the entrance hole from the inside and glued with commercially available sanitary silicone.