... -EN50291 Co Detector 3-Test Button with 3 LED indicators 4-LCD Displayer 1.85 decibel alarm sound. ... .Alarm beeps model -- four short alarm. Red,4.LED shining and panic mode."The clamorous" show "and" ... that the battery5.Low (need to replace) (green LED flash surveillance status is6.Every 30 seconds) or unit ... 7.If the memory, alarm device, warned,Green LED flash button, every second, once one Minutes, ...