Weatherproof Smart Driveway Alarm with Adjustable Detection and App Connectivity
$65.99
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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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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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Ring Alarm Motion Detector, 90 Degree Coverage 25ft Range, NEW, 2nd Gen (4-Pack)
$77.99
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5 Pack Water Leak Detectors - 100dB Alarm for Basement & Home Flood Alerts, Pipe
$79.99
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CLOUDY BAY Motion Sensor Ceiling Light 6.5 inch-5000k day light, 5000K
$27.83
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Savant AS-414, Auto Shut-Off Valve for Water Leak
$45.70
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Zircon Leak Alert Wi-Fi Water Detector - Clear
$10.00
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2 Pack Motion Sensor, 180-Degree Replacement Motion Detector for Outdoor Ligh...
$28.74
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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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SALE New 20m Single Beam Alarm Photoelectric Infrared Detector Alarm Home Security
$14.55$16.72
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Driveway Alarms Wireless Outside Weatherproof - Motion Sensor Alarms System Moti
$38.50
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Wireless Motion Sensor Plug Kits,No-Wire Mini PIR Sensor Switch Control Plug ...
$35.79
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1pair 100m Dual Beam IR Infrared Detector Module Burglar Alarm for Home Security
$37.69
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SALE AC 85-265V New Motion Infrared Sensor Switch For Outdoor 180° Detection Range
$11.54$13.42
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SALE DC 10 x RC-33 NC Wired Door Contact Sensor Alarm Magnet Reed Switch
$12.07$14.03
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SALE Automatic Light Sensor Control Switch DC8-50V Photocell Light Switch Accessories
$11.88$13.66
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SALE New ABS Water Leak Alarm Flood Level Overflow Detector Sensor Home Security
$9.72$11.30
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Motion Sensor Light Switch, No Neutral Wire Required, No Ground Wire Needed,5...
$25.91
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SALE 315mhz Infrared Motion Sensor Home Garage Alert Security System
$18.27$21.00
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GoveeLife Human Presence Sensor, 2.4 GHz Smart mmWave Radar & PIR | H5127
$23.99
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SALE Motion Sensor DC 5V 24V Light Switch Movement Detector Automatic PIR Sen B
$9.75$11.21
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SALE 3-5m Automatic Body Infrared PIR Motion Sensor Detector Switch For LED light B
$9.75$11.21
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SimpliSafe FIRST 1st GENERATION - 2 Wireless Keypads & Motion Sensor Lot
$49.99
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SALE White Smart Thermometer Hygrometer Wi-Fi Temperature Humidity Sensor Monitor
$18.58$21.60
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SALE 10 x RC-33 NC Recessed Door Contact Sensor Alarm Magnet Reed Switch
$12.33$14.17
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Sump Pump Alarm, High Leak Detection, 110dB Loud Alarm and LED Lights
$10.00
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Energy Converter, 5000W Modified Wave Transformer, 12V DC to 110V AC Vehicle Ada
$414.60
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Ademco Honeywell 4208U Universal 8-Zone Expander vplex v-plex (BRAND NEW sealed)
$55.00
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Honeywell FG-701 Glassbreak Simulator Flexguard Intellisense Tester Tool TESTED
$75.00
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NIB SimpliSafe ES3 Entry Door Window Sensor Magnetic White
$15.00
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Hardwired PIR Infrared Motion Sensor, Indoor Only, 100-130V, White
$5.00
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SimpliSafe Home Security System Panic Sensor Button (PB3)(SSPB3)
$8.00
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Sharkward motion sensor... Passive Infrared Fixture Integrated Sensor
$19.99
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Water Leak Detectors for Home, 120Db Water Sensor Alarm Leak Detector, IP66 Wate
$43.40
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SALE GoveeLife Water Leak Detector 1s with Smart Gateway 1s (1+ 4Pack) Read First ***
$47.99$59.99
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SALE Solar Wireless Driveway Alarm - 1/2 Mile Long Range Receiver Only NEW OPEN BOX
$14.99$19.99
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3 Pcs HC-SR501 PIR Infrared Sensor Human Body Motion Detector Module Black
$16.99
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Ubiquiti Networks mFi mFi-MSW Wall Mount Motion Sensor Used Good Condition
$11.99
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BS010L DC 12V to 30V 3A Mini Pir Motion Switch,Occupancy Switch for Safe, Kit...
$15.05
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Marine Battery Charger, 1-Bank, 10A 12V Onboard Boat Charger, IP68 Waterproof S
$107.29
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SENSOR MOTION PIR WIRELESS ALARM WITH 2 REMOTE CONTROLS SHED GARAGE HOME CARAVAN
$13.99
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NEW Aqara FP300 Presence Multi Sensor Matter Apple Home, Google, Battery Powered
$70.00
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SALE SimpliSafe SS3-KEYFOB Key Fob Remote for SimpliSafe Systems - Black
$18.00$20.82
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MC-31 Wired Surface-Mounted NC Magnetic Door Window Contact Sensor Alarm Reed Sw
$10.24
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SALE Wireless 110° PIR Motion Movement Sensor Detector Pet-Friendly Sensor 433MHz
$23.03$25.59
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Water Leak Sensor 3-Pack Water Detector Long Range No WiFi Smart Home System
$74.98
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