* Photoelectric sensing technology  
* Easy installation and maintenance  
* Battery case at the back of a sensor for easy removal of a battery
* Sleek low-profile housing design
* Low-battery warning
* Test button verifies battery and alarm operation
* Hush Button With temporary silence function(8mins)
* Sounding a loud alarm signal of exceeding 85 dB in alarm mode  
* Five-year limited warranty
Specifications

* Smoke Sensitivity:                  0.086 dB/m to 0.14 dB/m    
* Power Supply:                        9V Carbon Zinc/Alkaline/Lithium Batttery 
* Battery Life:                           >12months    
* Low battery life:                     >30days    
* Alarm indicator:                      continuously emitting red light and shounder          
* Alarm sound level:                  >85dB at 10 feet (3m)    
* Temperature:                          0℃ - 50℃    
* Humidity:                                10%-90%RH, no condensation or icing
* Dimensions (L x W x H):          Ø107x37 mm