... blue back-light display, voice prompt, ease of use. Support dual-network of both PSTN landline and GSM System Features 1 ... blue back-light display, voice prompt, ease of use. Support dual-network of both PSTN landline and GSM mobile network, provide ... be sent via SMS.15.Panel integrated with either dual-band, triple-band, quad-band GSM/GPRS industrial graded module, stable and reliable. Notice ...