This item is designed for the possible installation. This small gadgets will alert and warn people stay far from field when it detected . The adopts the special structure design and , has the , mothproof and outside light interference feature etc. Features - Color: White. - Material: Plastic - Size: Approx. 10.7 * 10.7 * 2.8cm/ 4.2 * 4.2 * 1.1 inch (L*W*H). - for durable and use. - Alarm test button for easy testing. indicator. Designed for the possible installation. - Alarm Indication: Red LED flash. This small gadgets will alert and warn people stay far from field when it detected . - Adopts the special structure design and , has the , mothproof and outside light interference feature etc. - Suitable for detect the in house, shop, hotel, restaurant, office building, school, bank, library, and etc. Technical Specification - 9V battery ( NOT Included ). - Sound Level:>=85dB/ . - Alarm Current: <=20mA. - Standby Current: 300mA. - Operating Temperature: -10 ~ +50 degreen. - Operating Humidity: 95%RH. - Detecting Area:20 square meter. - Sensitivity: 2.36%/ +/-1.251%/ OBS. Package list: 2 * -168 Alarm 85dB/ Beeping With Fire Alarm Warning and Photoelectric Sensor Battery Powered For Security Automatic Reset (White)