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Fully insert the SIM card into the SIM card slot, with the metal contacts facing down and the angled edge facing out.
Example of AT&T's IoT Sim card installed in a RediGate (note the three embedded SIM sizes: Mini, Micro, and Nano):
Step 4:
Gently slide the RediGate back into its enclosure and carefully replace the five mounting screws to avoid over-tightening.
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