iPhone XS Max A1921 (AT&T) Logic Board with Paired Face ID Sensors
Includes the paired earpiece speaker and front-facing camera assemblies.
Face ID sensors that are part of the earpiece speaker and front-facing camera assemblies are paired to the logic board in an iPhone XS Max. To retain Face ID will functions a logic board must be replace along with its paired components.
This logic board is "locked" to AT&T. If you wish to stay with your phone's original service provider you must replaced the logic board with one locked to the same provider.