... requirements.Indication of low battery voltage (LED light is always on).It is praise worthy that ... category. *There are two kinds of alarms, including sound & light and vibration. Features: 1, simple, convenient, easy to ... the price has advantage. 6, It has a sound, light alarm, and vibration alarm. 7, It is the ... 4, alarm mode: synchronized alarm of light and sound, vibration alarm. 5, weight: 260 g