The Elitebook 455 G7 supports LTE cards... However, if you purchase a unit without the LTE card and want to add it later, you need to make sure the configuration of the laptop includes WWAN antennas on the display, and this is configurable... When you order with the correct panel option, the antennas will be placed ready to tap onto the LTE card that will fit its m.2 slot
the service manual for this model provides all the answers you should need for your effort... do make sure you obtain the correct LTE module for you country
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