The BugDorm-4E insect rearing cages are cubic or rectangle cages of various sizes. They all use fiberglass to support the structure, making the cages lightweight and easy to carry and store. The fiberglass framework is constructed outside the enclosure, minimizing gaps for insects to hide. The bottom of these cages is soft. You can install the acrylic floor (sold separately) to support the bottom when carrying heavy items is required. The BugDorm-4E insect rearing cages use very dense fabric with a mesh aperture of only 160µm, which will effectively keep minute insects like Thrips from entering or escaping the cage.