@hangout Typically, for AT&T, it means you got a "multi-size SIM", which is essentially a "nano SIM", with a "plastic frame" around it, for use with devices that need larger SIMs (micro, etc).
For your iOS device, as mentioned, you'll end up using the nano SIM anyway...
*If this (or another post in this thread) fixes your problem/issue, please mark it as "accept-solution", and I'll tag it, to make it easier for others to find the answer(s). FYI: I'm an AT&T end-user, just like most of us in the forum. Thanks.
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