Wireless RS232 4G LTE Modem Serial Port Ec25 GSM GPRS 4G LTE M2m Industrial Modem - China RS232 4G 3G Modem and 4G Serial Port Modem price | Made-in-China.com
Amazon.com: PUSR (Price for 2 Pcs) GSM Modem Serial RS232 RS485 to GPRS DTU with at Command USR-GPRS232-730
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Modem GSM/GPRS, Robustel GoRugged M1000 MP, interfață RS232, comenzi AT