... , can achieve link detection and auto-redial. H6x21 GPRS Modem is designed for industrial applications based on 2.5G/ ... ºCRelated humidity: 95%(non-condensing)Ordering InformationH6221 Series GSM/GPRS modem has been used at many circumstances. Considering the application ... Dual band. +5VDC, +7. 5~26VDC Optional. GPRS MODEMH6221-WRS-232 Interface, Wavecom module inside, 900/1800 Dual band. +5VDC, + ...