520 00 my” CAT 3G 850 CAT Telecom
520 01 AIS GSM 900 Advanced Info Service
520 02 CAT CDMA 800 CAT Telecom
520 03 AIS 3G 2100 AWN
520 04 True Move H 4G LTE Real Future
520 05 dtac 3G 2100 DTN
520 15 TOT 3G 2100 Telephone Organization of Thailand (TOT)
520 18 Dtac GSM 1800 Total Access Communication
520 23 AIS GSM 1800 DPC
520 99 True Move GSM 1800 True Corporation
520 25 WE PCT PHS 1900 True Corporation
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