20M One Beam Infrared Sensor Detector Alarm Photoelectric Infrared Laser Sensor
$15.24
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Sensors & Motion Detectors
Motion, door/window and glass-break sensors are the trip-wires of a security system. Check what hub or panel they pair with (many are brand-specific and won't mix), wired vs wireless, and battery life for wireless units. For motion sensors, pet-immune designs avoid false alarms. Buying spare or used sensors is fine — just confirm the protocol and that they're compatible with your system.
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PIR Motion Sensor Switch Wall Light Switch For Installation Height: 1.8m To 2.5m
$14.09
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New 10ft-23ft Infrared Motion Sensor Home Garage Alert Security System
$19.15
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ismartgate Magnetic Wireless Sensor for Gates, Shutters and Roller Doors ISG-GWS
$42.00
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Motion Sensor Switch with Fresnel Lens AC100-240V for Track Lights & Spotlights
$12.49
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DC USB Body Infrared PIR Motion Sensor Switch Detector Switch For LED Light m
$11.27
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3-5m Automatic Body Infrared PIR Motion Sensor Detector Switch For LED light G
$10.33
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NEW Ring Alarm Motion Detector (2nd Gen) (2-Pack) - White
$39.99
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Panasonic KX-HNS102 Wireless Home Network Motion Sensor - New in Box
$16.95
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SALE 2 Pack Wireless Motion Detector Alarm, PIR Sensor for Pets & Intruder Alert, Ind
$71.99$79.99
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SALE Wireless Motion Sensor Alarm - 17 Chimes, 3 Modes, 110dB, 2 Detectors & Remotes
$71.99$79.99
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Interlogix Reed Switch Door Position Swtich Sensor Alarm Magnetic Lot Some Used
$39.99
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Outdoor Infrared Beam Sensor, Motion Detector Digital Photoelectric 328ft Range
$23.35
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ONE NEW Honeywell DT-6360STC DT6360STC Ceiling mounted dual detector
$253.27
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NEW! Swann Driveway Wireless Alert Kit Motion Detection Model SWADS-ALARMK-LW
$44.99
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GE Portable Wire-Free EZSmart Motion Sensor Z Wave Plus Monitor W/mobile
$24.29
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Safe House Invisible Pulsed Beam Infrared Photorelay Alarm 49-307 Radio Shack
$19.99
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SALE Mypropane | Propane Tank Monitor | No Recurring Fees | 4G/5G LTE | Solar Chargin
$277.09$325.99
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SALE Solar Outdoor Motion Sensor Alarm with Dog Bark Sound, 130dB Loud Noise Maker, 3
$89.99$99.99
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Wireless Driveway Alarm 1800 Feet Long Range Motion Sensor Alert System
$88.99
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SALE 20M Single Beam Detector Alarm Photoelectric Infrared Laser Sensor Anti Theft E
$14.77$16.23
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SALE New Automatic Light Sensor Control Switch DC8-50V Photocell Light Switch Parts
$12.07$13.26
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IR IR-D-P2E Indoor Dual Technology Motion Detector
$10.99
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SALE Motion Sensor DC 5V 24V Light Switch Movement Detector Automatic PIR Sen C
$9.90$10.88
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New Intermatic Motion Detector Sensor Hands Free Control Automatic Lights Switch
$7.91
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SALE New 10 x RC-33 NC Recessed Door Contact Sensor Alarm Magnet Reed Switch
$12.51$13.75
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SALE ABS 24.125GHz Human Inductive Motion Microwave Radar Sensor For Automatic Door
$18.91$20.78
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WiFi Water Level Monitor Alarm Float Sensor Battery
$139.66
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Well-Designed Flexible Maneuverable Portable Infrared Anti-Spy Security Detector
$37.69
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Honeywell Home SIXGB Wireless Glassbreak Detector 25' Range SIXGBA
$19.95
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X-Sense Water Leak Detector Kit, Smart Water Leak Sensor With Base Station
$70.00
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WiFi Water Level Monitor Alarm Float Sensor Battery
$154.00
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SALE 2pcs NC Recessed Wired Security Door Sensor Alarm RC-33 Magnetic Reed Switch
$15.38$16.19
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SALE 2pcs NC Recessed Wired Security Contact Sensor Alarm RC-33 Magnetic Reed Switch
$13.76$16.19
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2 Pack Water Leak Detectors, 100Db Water Sensor Alarms Flood Detector for Baseme
$22.01
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4 X GE Window/Door Alarm, 8 Total Audible Home Security Alarm, 45115, New Sealed
$29.99
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WiFi Water Level Monitor Alarm Float Sensor Battery
$154.00
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New Effective Device Water Leak Alarm Flood Level Overflow Detector Security
$10.41
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PIR Motion Sensor Switch Auto-Sensing On/Off AC100-240V for Schools & Buildings
$12.36
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2pcs PIR Motion Sensor Switch Wall Light Switch Delay Time: 5s~8min (Adjustable)
$13.94
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Smart Thermometer Hygrometer Wi-Fi LCD Temperature Humidity Sensor Home Digital
$19.89
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3-5m Automatic Body Infrared PIR Motion Sensor Detector Switch For LED light F
$10.22
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1Pc USB Port Detector Infrared PIR Motion Sensor Switch For Led Light Strip bb
$11.15
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Automatic Light Sensor Control Switch DC 8V-50V Photocell Light Switch Parts
$12.45
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12-24V 24.125GHz Human Inductive Motion Microwave Radar Motion Tracking Sensor
$19.52
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SALE Mighty Mule Wireless Driveway Alarm System - FM231 Open Box New
$52.99$58.99
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WiFi Water Level Monitor Alarm Float Sensor Battery
$154.00
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WiFi Water Level Monitor Alarm Float Sensor Battery
$154.00
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