Checkpoint button · WM-90A
iButton checkpoint button
A stainless iButton chip in a plastic wall plate, held by two screws. The reader has to touch it — no radio energy in the area, which is why this is the version used around fuel and chemicals.
- ✓Read-only DS1990A-F5 chip: the code is written at the factory and cannot be copied or edited.
- ✓Two screws instead of adhesive — the plate cannot be peeled off or quietly moved to another door.
- ✓Drill two 6 mm holes, push in the plugs, screw the plate down.
- ✓No battery and no radio: safe where a spark matters.
| Chip | DS1990A-F5 (iButton) |
|---|---|
| Interface | 1-Wire, contact read |
| Plate size | 47 × 32 mm |
| Chip size | ⌀16 × 5 mm |
| Fixing | 2 screws, 6 mm holes |
| Weight | 1.6 g |
