Window alarm are available like so:

GE 51107 SmartHome Wireless Alarm System Kit
Feature: ... 120-decibel alarm sounds when window or door is opened; Easy to install with no wiring necessary; Door alarm uses 4-digit keypad to set security code for arming/disarming; Alarm delay feature avoids false triggering; Three window alarms included ...more
Customer Reviews — [1] Rating: 5 Date: 2008-12-24 Summary: Good System ... This is a good system for those who live in an apartment or who does not want to pay a fee every month to have a security system. Very very easy to set up. I suggest you purchase the home security sighs as well. It will complete the package. ...more
[2] Rating: 4 Date: 2008-12-24 Summary: does what it says ... The window units as others have said are kind of lame since you can just close the window and the alarm goes off and there is an on/off switch for it! The door unit works very well. I have a little trim around my door that puts a little gap between the magnet and the sensor and it still works. It's also very loud. Who knows whether this will actually stop someone breaking in but at the very least it'll startle him and even if he does take off with your plasma TV, his ears will be ringing for a while. ...more
[3] Rating: 5 Date: 2008-11-25 Summary: Worked Well ... Not too expensive yet lets me know everytime one of my kids try to open the doors. Plenty loud, I call here it when I'm in the basement. Simple to setup as well. ...more
Editorial Reviews — ... Product Description | GE 51107 WIRELESS ALARM SYSTEM KITFEATURES DOOR ALARM DELAY OPTION;DOOR ALARM OPERATES IN BOTH ALARM and CHIME MODE; USER-DEFINED SECURITY CODE FOR ARMING and DISARMING ALARM OR CHIME FUNCTION; DOOR ALARM REQUIRES 3 AAA BATTERIES and EACH WINDOW ALARM REQUIRES 4 LR44 BATTERIES; INCLUDES DOOR ALARM and 3 WINDOW ALARM...more

Mini Window Alarm w/ Deactivation key - Set of 3
Feature: ... 105 dB alarm - only 2 1/2 inches long; Magnetic sensor to detect opening of a protected window; Insert deactivation key to open protected object without setting off alarm; May also be used on Cabinets, Sliding Glass Doors, Cash Registers, & Showcases; Batteries included ...more
Editorial Reviews — ... Product Description | At only 2 1/2 inches long, the world's smallest window alarm inconspicuously protects your home from intruders. This unit uses a magnetic sensor to detect the opening of a protected window. A 105 dB alarm will then alert you to an attempted entry and scare off potential intruders. The owner may open the window or other protected object, without setting off the alarm by inserting a deactivation key. Once the deactivation key has been removed and the protected door or window is opened, the...more

Mini Door & Window Alarm
Feature: ... WINDOW ALARM; KW's: window alarm security device ...more
Customer Reviews — [1] Rating: 5 Date: 2006-08-03 Summary: It does it's job! ... This little alert does exactly what it is designed to do. For use as a warning that a particular window or door is being opened. I use it on a back bedroom window and it gives my wife an I just a little more security for very little cost. Also can make an intruder think twice, wondering who it might be alerting. ...more
[2] Rating: 5 Date: 2007-06-16 Summary: GREAT ALARMS ... VERY VERSITILE ALARMS, CAN BE USED AT HOME OR FOR TRAVELS. I BOUGHT THEM FOR THE DOORS THAT LEAD TO THE POOL SO THAT SMALL CHILDREN CANNOT OPEN THE DOOR AND DROWN IN THE POOL WITHOUT A LOUD SHREEKING ALARM GOING OFF. YOU CAN DISABLE AND ENABLE THEM WHEN YOU WANT. I WILL ALSO FEEL SAFER IN A MOTEL ROOM NOW. THE ALARM IS VERY LOUD. ...more
Editorial Reviews — ... Product Description | Provides alarm security to door, window, sliding glass door, or potentially dangerous cabinet or closet. Alarm sounds when magnetic contact is separated. Ultra loud 105 dB. Key to arm disarm unit....more

ZOpid - 2-in-1 Motion Detector and Door/Window Contact Sensor Mini Alarm System - HS-ZMA55
Feature: ... Alarm can be set for motion detection or door/window sensor, or both (user selectable); Wireless - simple installation - Mount alarm using 3M Tape (included) or Hardware Mounting Kit (included); 30-seconds entry and exit delays prevent false alarms - Create your own four digits security code; Automatic reset once motion is no longer detected for 30 seconds; Low battery level indicator - Uses 3 AAA batteries (not included) - One-year battery life ...more
Editorial Reviews — ... Product Description | KEY FEATURES Alarm can be set for motion detection or door/window sensor, or both (user selectable) Wireless - simple installation Mount alarm using 3M Tape (included) or Hardware Mounting Kit (included) 30-seconds entry and exit delays prevent false alarms Create your own four digits security code Automatic reset once motion is no longer detected for 30 seconds Motion detection range about 20 feet (6m) Low battery level indicator Uses 3 AAA batteries (not included) One-year battery life...more

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Door And Window Alarm, KEEP YOUR HOME SAFE.

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