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Multiple sensors based fire extinguisher robot based on DTMF, bluetooth and GSM technology with multiple mode of operation | Semantic Scholar
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ASIMPLE ROBOT】Smallest SIM800L GPRS GSM Module MicroSIM Card Core BOard Quad-band TTL Serial Port with the antena - AliExpress
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SIMPLE ROBOT】SIM800C GSM GPRS module STM32 microcontroller 51 equipped with For Bluetooth and high- TTS - AliExpress
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