The 3-element top entrance gate is a valve to limit the size of the top entrance to the hive.
It consists of 3 galvanized metal plates, the fixed part is the body, in which two
movable gates, one of which has cutouts to restrict the passage of bees, the other with small holes
for ventilation.

material:
galvanized steel 0.5 mm.

dimensions:
width - 45 mm
length - 145 mm
weight - 0.052 kg.