Here's the same list again, ordered by code.
MB123XX/A or MC123XX/A is the device code and
XX is the regional identifier (or however it is called). This code you can find in this list:
AB Egypt (Mobinil, Vodafone, Orange), Saudi Arabia (Mobility), United Arab Emirates (etisalat)
B Ireland (O2), UK (O2)
C Canada (Rogers, Fido)
CZ Czech Republic (O2, T-Mobile, Vodafone)
DN Austria (T-Mobile), Germany (T-Mobile), Netherlands (T-Mobile)
E Mexico (Telcel)
EE Estonia (EMT)
FB Luxembourg (LUXGSM, Tango)
FD Austria (One), Liechtenstein (Orange, Swisscom), Switzerland (Orange, Swisscom)
GR Greece (Vodafone)
HN India (Airtel, Vodafone)
J Japan (SoftBank)
KN Norway (NetcCom)
KS Finland (Sonera), Sweden (Telia)
LA Colombia (Comcel, Movistar), Ecuador (Movistar, Porta), El Salvador (Movistar, Claro), Guatemala (Movistar, Claro), Honduras (Claro), Peru (Claro, TM SAC)
LE Argentina (Movistar, Claro)
LL USA (AT&T)
LZ Chile (Claro, TMC), Paraguay (CTI Movil), Uruguay (Movistar, CTI Movil)
MG Hungary (T-Mobile)
NF Belgium (Mobistar), France (Orange), Luxembourg (Vox Mobile)
PL Poland (Era, Orange)
PO Portugal (Optimus, Vodafone)
PP Philippines (Globe)
RO Romania (Orange)
RS Russia (Beeline, MegaFon, MTS)
SL Slovakia (Orange, T-Mobile)
SO South Africa (Vodacom)
T Italy (TIM, Vodafone)
TA Taiwan (Chunghwa Telecom)
TU Turkey (TurkCell, Vodafone)
X Australia (Optus, Telstra, Vodafone), New Zealand (Vodafone)
Y Spain (Movistar)
ZA Singapore (SingTel)
ZP Hong Kong (3), Macau (3)
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