Get the incredible wireless door and window alarm now and protect your home against intruders! It works with magnetism. It s activated when the door or window is opened and the two parts with magnets of this security alarm are separated. Powerful sound of 100 dB. Easy to install (adhesive element included). No need for cable or electricity. Battery-operated (2 x AAA, not included). Measures: Approx 3 x 9 x 2 cm.