We don't have a regular SIM card in Trax. It's a M2M eSIM that's mounted directly on the PCB. Reason is to win size and that you can get better M2M prices. In this way we can sell Trax for £149 with 2 years of data and roaming included in the price.
After two years, the fee for roaming is $5/month. It's paid through WTS - the company behind Trax.
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