... 1.DC12V battery 2.dustproof meshwork 3.SMT design,high stability 4.infrared photoelectronic sensor wireless fire alarm smoke detector1.TECHNICAL ... -LIGHT,MOTHPROOF,DUSTPROOF•STRONG ADAPTABILITY FOR CIRCUMSTANCE•SMT DESIGN,HIGH STABILITY•STAIN STEELESS SHIELD,ANTI-RFI(20V/m-1GHz)