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An eSIM is a SIM card permanently soldered onto a device’s circuit board during manufacture. It does the same job as a removable SIM card, but there is no slot that can loosen, corrode, or fill with water in the field. For a small asset tracker installed in a shipping container, this matters.
The MFF2 form factor (5×6mm, machine-soldered) is the industrial standard for eSIM. The carrier profile can be updated remotely via the GSMA SGP.02 standard – operators can switch network providers without physical access to the device.
- Eliminates the mechanical SIM slot – the most common field failure point in harsh environments
- IP67 and IP68 enclosures are simpler to design without a slot penetration
- Remote SIM provisioning allows carrier switching without visiting the device
- Used in compact asset trackers and IoT sensors where ruggedisation is more important than easy field swap