The product with infrared sensor detects infrared radiation from human body nearby and send alarm sound. It can be used in doorway, warehouse, backyard …etc.When someone approach its range ,it will emit alarm sound to alert you. Material:ABS Remote distance:6m Detectiondiatance:up to 6m Detection range: Angle of 90 degree Power supply: 4*1,5V AA battery(Not included) Remote control battery: 3*LR44 battery(included) Package includes:1X Receiving body,2xRemote control(6xLR44 battery included) and 1xBracket