... : 900, 1800, 1900MHZ·Embed four condense microphone·All GSM SIM card compatible·Microphone range(Meter): 5~7(Radius), 4 levels·Receive ... is fully charged up, only Red LED lightsON·Place the SIM card into the slot with the contact points facing down ( ... indication)·The flash of red light indicates the SIM card is correctly inserted. SIM will completed initialization andmaintain in stand-by status ...