Switchable Bee Escape

I have seen this one in the Thomas Bee Appliance catalogue. But the picture was small and indistinct.

I will pursue better illustrations and detailed drawings.

It is intended for installation in a board such that the operating plunger protrudes through the rim of the board itself. This gives two way bee traffic with the plunger pulled out and one way action when in the fully inwards position.

To date I have not seen or handled an actual example.