... ergonomic design, lightweight and flexible, shock drop resistance, long standby time, dual power mode, also with call feature. The ... ,GSM27.10 Power Source(Dual power source mode)Operating Power3.7V 2800mAh Rechargeable BatteryBackup Battery150mA,retain data ... to concrete, room temperature and default configuration; multiple 1.2M drops to concrete, all axis, and across operating temperature range ...