Engineering
We drop every case before you do.
Protection you can measure starts with a repeatable test. Here is how the drop program runs — corner-first onto steel, re-checked across the hinge axis — and the figures each tier earned.
The test
How we test.
Each tier is drop-tested corner-first from its rated height onto steel. Corner-first because a corner concentrates the whole fall into the smallest possible contact patch — the worst case for the frame and for both displays.
Then we re-check across the hinge axis, where a fold is most vulnerable: the one moving seam a slab phone never has. A case that holds on a flat drop can still fail here, so the hinge cover earns its own pass on the bench.
Every rating is bench-verified before a case ships, and the height is set per tier — a Slim shell and an Ultra shell are never asked to survive the same fall. Same procedure, run the same way each time, so the numbers stay comparable.
The record
The record, tier by tier.
Four rungs on the ladder, four sets of numbers. Every figure below is a measured drop height, thickness, and weight — read straight off the spec of each tier's representative case.
| Tier | Drop tested | Thickness | Weight |
|---|---|---|---|
| Slim | 8 ft | 1.4 mm | 32 g |
| Rugged | 16 ft | 2 mm | 48 g |
| Ultra | 32 ft | 2.6 mm | 61 g |
| Designer | 12 ft | 1.8 mm | 44 g |
Sample figures — illustrative until substantiated by test data.
Materials
What the case is made of.
Three materials, each doing one job. The shell holds its shape, the weave takes the impact, the sidewalls take the shock — layered so the load never lands on any one of them alone.
- Aramid weave
- A high-tensile aramid weave forms the impact core and the reinforced hinge axis — the fiber that takes the corner-first load and spreads it before it reaches the frame.
- Polycarbonate
- A rigid polycarbonate shell holds the case's shape and distributes a flat drop across the whole back, so no single point carries the hit alone.
- Soft silicone
- Micro-textured silicone sidewalls absorb the residual shock and add the grip that keeps the fold off the edge of the table in the first place.
Anatomy
Anatomy of the hinge cover.
The five-sided hinge cover is the part built first and the part every other decision is made around. It wraps the fold's weakest axis on all five exposed faces, leaving only the seam the phone needs to close — so the moving edge is protected without fighting the fold.
The Z Fold care guide
Hinge care, cleaning, and install — field notes for the fold.