Features:1.The photoelectric technology, it is more sensitive in detecting slow smoldering fires which generate light smoke, little heat and may smolder for hours before bursting into flames. This smoke alarm does not contain any radioactive material.2.Easy installation battery offers continuous protection for the life of the smoke detector even during power failures.3.Silence button to verify the unit's electronic circuitry, horn, and battery functions are working properly. 4.During a smoke incident, the smoke alarm will sound in a repetitive manner. Attantion:1.As the battery in this unit is not replaceable, a low battery signal is an indication of end of life. Therefore the alarm MUST be replaced as soon as possible!2.The smoke alarms should be installed in every room, except the bathroom and kitchen.3.These guidelines will assist you in the event of a fire, however, to reduce the chance that fires will start, practice fire safety rules and prevent hazardous situations. Specifications:1.Mini design, Size: f2.82 * 1.35inch2.10 years long life time3.Big button for easy pressing(Test/Silence button)4.Full circle alarm LED light5.Loud>85dB(A)alarm signal @3M6.Stainless steel metal decorative loop7.10 Hours non-disturb mode under low battery status8.Wireless base for option9.High quality metal net Suit10.Automatic compensation design with stable performance, suitable for long life operation, lower false alarm rateMore Detail See User Manual