SmartLINK: Compatible via the Ei3000MRF Module; Up to 12 units can be interconnected via a hardwired or wireless system (using optional Ei3000MRF SmartLINK module) This is the Aico Ei3028 is a dual sensor alarm - Heat and Carbon Monoxide (CO) alarm. It contains a proven electrochemical CO sensor that detects the presence of toxic levels of Carbon Monoxide, as well as an independent fast acting Class A1 Thermistor sensor to detect dangerous levels of heat. This alarm is a multi-sensor fire alarm - it contains both a CO sensor and a fire sensor, thus detecting both the presence of toxic levels of Carbon Monoxide and of heat, providing protection from both fire and CO in one alarm Indicator LED’S: Green – power. Red – pre-alarm (CO only)/ alarm/ silence mode/ memory or battery event. Yellow – fault event Silence Function: Silences alarm for 10 minutes if alarm is triggered by heat or once for 4 minutes in case of CO event.