AD22 series of indicator is equally used LED shining chip as its light source. The covers with technique of high polycarbonate have good anti-surge performance. It has the characters of low consumption, small volume, light weight and long life (50, 000¡ª100, 000 hours). Meanwhile, we have developed corresponding series of shining buzzers and flash lamps. According to the requirements, we can choose different light source; Which expand the range of application.