This product is easy to install? simply pasted on the host machine door Vice Admiral pasted on the door or on the two windows ? auxiliary machinery arrow mark aligned with the host side . When someone illegally open door or window when ( main and auxiliary parts separated more than 10mm)? the alarm will be issued > 90db siren to warn the intruder to leave. They have to open the door when the window switch can be controlled . Use 3 × 1.5vlr44 button batteries ( included Pat machine ) . The security alarm on the door or window ? the thief want to open the door or window ? the alarm will sound an alarm immediately ? the switch can be turned off when not in use. Application of magnetic induction alarm control technology ? long life ? easy to install . Using adhesive paste ? no screws ? can be pasted directly use ! Without damaging household items ! ( Also can be installed in the cafe computer chassis? computer hardware to prevent theft ) Usage: can be installed on windows and doors? a switch ? when the switch is turned on ? if the doors are opened ? a loud alarm will sound . Sleep at night or when not at home ? when out of the office ? the alarm switch is open ? the security alarm . Usage: alarm consists of a large and a small piece composition? the alarm size pieces were attached to the sides of the gap in the middle of two windows ? large and small pieces arranged in parallel ? middle gap size pieces so as not more than 5 mm ( can refer to the packaging looks good paste ) ? small pieces with an arrow ? the arrow in the opposite direction to the large and bulky parallel posted on the good ? to security? closed the window ? ? Chi ? ┥ ? epiphyseal ? Dian pure ? ? if thieves push the window ? as long as the window opened ( ie alarm large and small pieces of more than one separate 5 mm ) ? the alarm will send a strong warning sound ? the master of the house will take immediate action ? the thieves will be caught on the spot live or fled.