... 32SMS, MMS, TCP Protocol, remote control850/900/1800/1900 Key Features♦Just like 32 single-channel equipments ... chassis, elegant shell♦GSM frequency: 850/900/1800/1900 MHz♦32 x SIM card(big/small) slots♦ ... Feature ♦upport dual band:900/1800 MHz or quad-band GSM: 850/900/ 1800/1900 MHz♦ Meet the ETSI GSM 2 ... + standards♦ Class 4 ( 2W @ 900 MHz) Class 5 ( 1W @ 1800 MHz)♦5 -24 VDC power supply (which be ...