Zte Axon 7 Mini User Manual page 11

2. Place the nano-SIM/microSDXC card on the tray with the
gold-colored contacts facing down. Then carefully slide the
tray back into place.
nano-SIM 1 (right)
nano-SIM 1 (right)
and microSDXC (left)
NOTE:
When two nano-SIM cards are installed, pay attention to the
following restrictions.

If one nano-SIM card connects to 4G LTE, the other card can
only connect to 3G or 2G networks.

You can use either card for mobile data service. See
the nano-SIM Cards

If one card is connected to a phone call, the other card is
unreachable.
and 2 (left)
or
on how to switch.
11
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