Product information: – Color: Silver and black – Material: Stainless steel cover, ABS – Working modes: Vibration sensor. – Three sensitivity: High, medium, low. Contents in Box: – 1 x Door Stop Alarm More information about product: – Wedge-shaped design alarm stops intruder from opening door. – Easy to operate, just put it under the door. – Adjustable sensitivity switch prevents tampering. – Features 3 sensitivity levels and extra-loud alarm. – 120dB high-pitched continuous siren when it is enabled. – Dual Function: This alarm can be a door stop alarm or a door stopper, when the alarm being triggered and the meantime it will keep the intruder outdoor from you, it is safe. If the door is installed very high and far from the ground,please put a soft thing under the door stopper. – Extremely Loud Alarm: 120 dB loud belongs to Unbearable Noise and really loud. Easily can wake the homeowner up, notifies neighbors and scare the intruder away. Please do turn on the power button after set the battery well, then put the door stopper under the door. – Easy Install: No wiring needed, just put 9v battery in and switch the button on the back to ON then it can works. The bottoms are made of synthetic rubber for keep the alarm from slipping. – Light-Weight : Only 95 grams each stopper – without battery and package, good for carrying when you are travelling or need spend a night at strange environment. – 3 Sensitivity Levers: Low – Medium – High,with an adjustable sensitivity switch on the side,H level is the most sensitive level that vibration will trigger an alarm,please note when the alarm sound gradually becomes smaller,it means to replace the new battery.