This rim is placed between the outer cover and your top super to create a 1 1/2" space. The same size as our wooden hives, but can be used on BeeMax hives as well. They come unassembled, but are pre-drilled and include screws. The entrance can be sealed with a plug which can be removed for a winter entrance or for ventilation in the summer.
The 10 frame shim fits both 10 frame wooden hives and BeeMax hives.