Iridium extreme ptt User Manual page 226

SOS function works only in Phone Mode and not in PTT Mode. Switch to
Phone Mode to send SOS messages. Valid SIM, Airtime subscription and
proper SOS set-up required for SOS to function. Failure to satisfy these
conditions will prevent SOS from functioning, which could prevent or
delay an emergency response and result in serious injury or death.
Before dialing 911 or any other emergency services number, switch to
Phone Mode. A valid SIM card and Airtime subscription are required for
phone services.
The Iridium Extreme® PTT device purchaser is responsible for informing all
users on the proper usage and capabilities of each Iridium Extreme® PTT
handset.
If you are unsure whether your Iridium Extreme® PTT is configured for
Phone Mode, check with your Iridium service provider and make a test
call to confirm status. For information on how to obtain the Phone Mode
services capability, contact your local Iridium service provider.
220 Iridium Extreme® PTT User Manual
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