Model: SIM800L. With the SIM800L you get a powerful GSM module. 1 x SIM800L Module. GSM 2/2 standard. 7S 29.4V BMS Protection Board with Balance 18650 For Li-ion Lithium Battery USE. 10S 36V 15A Lithium Battery Protection Board Li-ion Cell 18650 Power BMS PCB.
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