Window magnet are available like so:

Magnet Door Alarm
Feature: ... Color Black ...more
Editorial Reviews — ... Product Description | This compact, attractive Magnetic Door/ Window Alarm uses magnetic affinity to initiate its 110 decible siren. The base of the alarm is bolted to door or window frame, the actuator is connected to the window or door. The alarm is activated by opening the door or window. Great for any door or window, particularly those hard to protect sliding glass doors. Requires 3 lithium button cell batteries (included). Available in Black...more

GRI MC25 WINDOW CHANNEL MAGNET (5-PACK)
Feature: ... Arrow marks polarity; Rare earth magnet; Designed to be mounted in the track of aluminum windows and sliders.; Fits most aluminum tracks.; No drilling required. ...more

10 Surface Mount Security Alarm Window Contact, Magnet

12 WIRELESS DOOR & WINDOW SECURITY ALARMS Magnet Alarm

WINDOW MAGNET flying MONARCH BUTTERFLY glass FLY-THRU

BAG 10 3/8 RECESS WHITE DOOR WINDOW CONTACTS /MAGNETS

10 Surface Mount Security Alarm Window Contact, Magnet

WINDOW MAGNET - SOCCER BALL fly-thru glass effect

WINDOW MAGNET - FOOTBALL fly-thru glass effect

WINDOW MAGNET - BASEBALL fly-thru glass effect

ADEMCO Lot - Motion and Door/Window Detectors & Magnet

WINDOW MAGNET - BASKETBALL fly-thru glass effect

WINDOW MAGNET - ORANGE DOUBLESIDED FISH fly-thru glass

NEW Windows of the World LOT 2009 16 mo with Magnets!

NEW SEALED ENTRY ALARM DOOR/WINDOW GUARD MAGNET SENSOR

36 WIRELESS DOOR & WINDOW SECURITY ALARMS Magnet Alarm

24 WIRELESS DOOR & WINDOW SECURITY ALARMS Magnet Alarm

4 WIRELESS DOOR & WINDOW SECURITY ALARMS Magnet Alarm

3D Pass Thru Magnets Window Screen 2 ANGELS Cherubs NEW

SET OF 6 EAGLE WINDOW MAGNETS REALISTIC RUSTIC WILDLIFE

3-1963 CHEVY CORVETTE SPLIT WINDOW MAGNETS 63 64 327

4 ADEMCO 5899 MAGNETS WITH SPACERS NEW DOOR WINDOW

Vintage Style WHAMO MAGIC WINDOW Toy Box MAGNET #3

Magnet Door Window Alarm Magnetic Open Alert Home Siren

WINDOW MAGNET - ELEPHANT fly-thru glass effect

WINDOW MAGNET - FLYING ANGEL fly-thru glass effect

WITCH Window Magnet FLY THRU Wicca Witchcraft PAGAN

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