Per-cage load capacity is the weight the bottom plate and mesh body can bear when one cage is fully loaded; it mainly depends on the base frame, bottom-plate structure, wire diameter and mesh density. A base with a perimeter frame and reinforcing ribs has clearly better load capacity than a pure wire-mesh structure.
Wire diameter and mesh opening are a paired set of parameters: the thicker the wire, the stronger each single wire; the denser the mesh, the more the load is dispersed. Together they determine the mesh body's deformation resistance; when holding small, heavy items, the mesh opening must not be too large, or the bottom will bulge.
Stacking load capacity is a separate set of parameters: in the stacked state, the bottom cage must bear its own cargo plus the entire weight of all upper layers. Stacking load is determined by post tube diameter, wall thickness, stacking feet and weld quality; when buying a multi-layer stacking solution, be sure to confirm the stacking load—not the per-cage load.
To judge whether the load meets the standard: first, check whether the factory load rating clearly distinguishes per-cage load from stacking load; second, inspect the workmanship at key load-bearing points (post-to-bottom-plate welds, stacking feet); third, see whether sampled load testing can be provided. Place the bulk order only after all three pass.
In actual use, keep a safety margin relative to the rated load; extreme full-load stacking is generally not advised. For heavy loads or impact loading/unloading, tell the manufacturer in advance so it calculates the structure according to the actual operating conditions.