(6) Honeywell Home 5816 2-Zone Door/Window Txmtters, White
$90.00
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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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Indoor Motion Detector Alarm with Remote Control, 110dB Alert, 4 Volume Levels
$49.99
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SimpliSafe ES3 (5-Pack) Entry Door Window Sensor White 3rd Generation Brand New
$40.00
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Aqara Motion Sensor P1 Requires AQARA HUB 5-Year Battery Life Pack Of 3
$59.99
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Simplisafe Motion Sensor-Gen 3-White-New in Original Box-Never Used
$24.95
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GE Personal Security Motion Sensing 120 dB Alarm / Entry Chime w/ Remote 51207
$24.99
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1pair 100m Dual Beam IR Infrared Detector Module Burglar Alarm for Home Security
$37.69
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Sump Pump Alarm, High Leak Detection, 110dB Loud Alarm and LED Lights
$10.00
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5 Pack Water Leak Detectors - 100dB Alarm for Basement & Home Flood Alerts, Pipe
$79.99
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Simplisafe Motion Sensor-Gen 3-White-New in Original Box
$17.00
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8 Pack Door Stop Alarm 120dB Security Wedge Stoppers for Home Travel Safety Tool
$53.99
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Temperature Sensor - Hot/Cold Detection - Compatible with Home Security System
$42.55
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Weatherproof Smart Driveway Alarm with Adjustable Detection and App Connectivity
$65.99
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Zircon Leak Alert Wi-Fi Water Detector - Clear
$10.00
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2 Pack Wireless Motion Detector Alarm - PIR Sensor for Pets, Dogs & Intruder Ale
$79.99
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New SimpliSafe SD3 Smoke Detector Alarm SSSD3 White
$30.00
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ADT Base S501R0-01 White D2 Smart Home Hub Security System Component Brand New
$30.00
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X10 Powerhouse Big Red Emergency Panic Button KR15A for X-10 Security Alarm
$12.00
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110V US Plug Industrial Smart Over Temperature Alarm Sensor Machine 752°F
$140.00
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Cooper VS310U-W Vacancy Sensor Switch, Single-Pole or 3-Way, 1000W/VA - 120V/AC
$33.99
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SALE US Shipment 3pcs Pet-Friendly PIR Motion Sensors For WIFI 4G Alarm System White
$53.85$57.29
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CQRobot 5.8GHz Doppler Motion Sensor
$20.00
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SALE Door Alarm for Kids 120dB Pool Safety Alarm Sensor 6 Pack Door Window Alarm
$47.45$51.58
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SALE ADT Motion Sensor SSM5R0-29-WH New Sealed
$12.00$12.50
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Protect Your Home with This 120dB Window and Door Alarm - Easy Setup, White
$15.18
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Safe House Invisible Pulsed Beam Infrared Photorelay ︱ Alarm 49-307︱ Radio Shack
$40.00
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Ademco Honeywell 4208U Universal 8-Zone Expander vplex v-plex (BRAND NEW sealed)
$55.00
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10.525GHz Doppler Microwave Motion Sensor for Raspberry Pi & Arduino - 16m Range
$36.99
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Bunker Hill Wireless Security Alert System Item 62447 New Open Box 400ft Range
$19.99
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SALE $9.89$10.99
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Microwave Leakage Detector HTI HT-M2 9v Battery
$12.00
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SALE Leviton 110C4-100 100 Pair Phone Wiring Base 110-Type Mount Patch Block w/ Legs
$42.74$44.99
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QTY-2 New Simplisafe Motion Sensor Gen 2 - White CA001
$39.95
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Mr Beams 2Pack MB330 Wireless LED Spotlight with Motion Sensor, Photocell,White
$50.00
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Eve Water Guard Smart Home Connected Water Leak Detector - Apple HomeKit BT App
$70.00
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Non-APP Wireless Driveway Alarm — 1/2 Mile Solar Motion Sensor with Plug-in R...
$72.17
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SALE 1/2 Mile Wireless Driveway Alarm - Robust Weatherproof Motion Detection Sensor
$94.04$98.99
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Hard-Wired Motion Sensor Ceiling Lights, 9in 20W Flush Mount 2 Packs, White
$42.79
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HULPPRE Solar Outdoor Motion Sensor Alarm-13 Sounds Including Medium, Yellow
$33.11
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Defiant 180 Degree Motion Security Light White
$67.23
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Outdoor PIR DC 12V Automatic Infrared PIR Motion Sensor Switch for LED Flood Lig
$12.83
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Solar Outdoor Motion Sensor Alarm - Dog Barking & Gunshot Sound 130db Motion ...
$37.92
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GTO FM139 Exit Wand - Compatible with Mighty Mule FM138 Vehicle Sensor - Linear
$79.99
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RAPICCA Wireless Door and Window Contact Sensor Alarm, Anti-Theft Burglar Alarms
$12.99
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X-Sense SWS54 Smart Water Leak Sensor Alarm With Base Station
$35.45
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Vintage Radio Shack Safe House Invisible Beam Intrusion Sensor 49-551a
$12.98
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Door Window Sensors XHS2-TY , XHS2-UE Home Comcast Xfinity Security MCT-350
$16.88
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Solar Outdoor Motion Sensor Alarm - Dog Barking & Gunshot Sound 130db Motion ...
$36.56
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