New and high quality. Suitable for windows or doors. Ideal entry warning for homes, apartments, mobile homes, offices, hotel rooms, garages, and more. Super loud 95 dB alarm. When someone opens the door or window illegally (the relative position of the primary and secondary parts changes), the alarm will sound a strong alert to warn intruders and notify the owner. This magnetic sensor detects the status of your door or window. It helps prevent children from sneaking out and enhances safety for homes, garages, mailboxes, and businesses. Easy to install and operate. Press the on/off switch to activate or deactivate the device, then insert batteries (batteries not included). Remove the self-adhesive pad on the back of the door alarm sensor and attach the alarm to the desired location. Offers excellent environmental suitability and stability. Package includes: 2 x Magnetic Sensors; 2 x Magnetic Sticks.