Features:Professional Carbon Monoxide Meter: adopts high reliability electrochemical sensor and controlled by microprocessor, the meter features of stable operation and sensitive response.Simple Installation: counterclockwise open the back cover and install 2pcs AA battery, after put the cover back, you can mount the detector on the wall by the included screws and anchors or stick it on the clean surface by the double-side tape.Compact Size Simple Solid Design: perfect fit for your modern style house, you can install it on the bedroom, living room, bathroom, etc(it is not recommended to install in the garage, kitchen, or furnace room).Applications: it is used in places where CO gas might leak to avoid dangerous accidents and ensure personal and property safety.Specifications:Material: ABSStatic Current: 15uAAlarm Current: 10mAWarning Concentration: 200ppmAlarm Decibels: 80dBOperating Environment: -20~50, 15~90%RHPower Supply: 2 * 1.5V AA battery (NOT included)Item Size: 105 * 105 * 40mm / 4.13 * 4.13 * 1.57inItem Weight: 106g / 3.73ozPackage Weight: 139g / 4.90ozPackage Size: 11.5 * 10.8 * 4.5cm / 4.53 * 4.25 * 1.77inPacking List:1 * Detector2 * Screw2 * Anchor1 * Double-side Tape1 * Manual (English)