• The Apple SIM is a multi-carrier SIM card that Apple offers. Apple boasts about itself in its own marketing copy:
• With the Apple SIM, you can choose from a choice of short-term plans from various carriers in the United States and the United Kingdom [and now other countries] straight on your iPad. So you can pick the plan that works best for you whenever you need it, with no long-term commitments. You may also be able to choose a data plan from a local carrier for the duration of your trip when you travel.
• The Apple SIM is the same dimensions as a Nano SIM (12.3 mm by 8.8 mm by 0.67 mm), but it's only compatible with certain iPad models that have cellular capabilities.

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