2 PACK WINDOW ALARM HOME SECURITY EASY TO INSTALL BATTERY POWERED This handy little alarm will allow you to protect yourself and your house for no cost. No tools needed for installation, no wiring required, no hassle involved with installation like expensive alarm security systems. No monthly monitoring service expense. The alarm will mount securely on any surface with included adhesive backing. It has magnetic sensor to detect opening of a door or window. When the alarm sensors are separated very loud 90 db alarm is heard. It lets you know that a door or window is opened, and scare off potential intruders. You may open the window, door or other protected object without setting off the alarm by switching the on/off switch to the "off" position. May be used to protect a gun or medicine cabinets, sliding glass doors, etc. What you get: 2 alarm sets in retail blister packs (batteries included).