Asus Zenfone Max (M1) ZB556KL was officially announced in October 2018 , Device released in October 2018 Asus Zenfone Max (M1) ZB556KL made under Zenfone.Mobile Network Support and BandAsus Zenfone Max (M1) ZB556KL have Dual, (Nano Sim) Card Slots, Asus Zenfone Max (M1) ZB556KL support all GSM Based network providers. Asus Zenfone Max (M1) ZB556KL mobile device support 2G Band Frequency at GSM 850,GSM 900,GSM 1800,GSM 1900 and Hight Speed