New DEFIANT Wireless Smart Water Leak Detector SWLZ20BWB w/4" Sensing Cable
$19.99
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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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2GIG 2GIG-DW20R-345 WIRELESS RECESSED DOOR TRANSMITTER GC2 EDGE QOLSYS iQ4
$18.95
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Automatic Motion Sensor Light Switch Set for Bathrooms & Garages - 2-Pack
$151.99
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Solar&USB Motion Sensor Alarm w/ Remote, 130db Sound Light Alarm Animal Repeller
$31.63
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SALE Wired Door Contact Sensor Black Garage NC Surface Mount Magnetic Reed Switch
$13.25$14.72
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Vintage GE Zonar Battery Operated Burglar Alarm
$29.99
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Honeywell Resideo SIXGBA Wireless Glass Break Detector
$24.99
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JMDHKK K18+ Anti Spy RF Bug Trac GPS Signal Detector Hidden Camera Finder NEW OB
$50.00
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Elegant White Maestro Motion Sensor Light Switch with Occupancy/Vacancy Modes
$86.99
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Water Alarm Convenient Water Reliable Water Leak Detectors for Household
$13.03
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Superior Pump Remote Water Detector with temp,humindity,and early warning alerts
$35.00
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Motion Detector Sensor Pet Immune 55 Honeywell DT-720B DUAL TEC Microwave
$27.99
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Water Leak Detector Sensor Alarm: Home Water Flooding Monitor Smart Sink Overfl
$16.36
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SALE DC12-24V 8A Automatic Adjustable Motion Sensor IR Infrared Detector Light Switch
$7.97$8.39
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Photocell Sensor with Base, Auto on off Photo Control & IP65 Photoelectric Senso
$28.05
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SALE High Precision Thermometer Hygrometer Wi-Fi Temperature Humidity Sensor Monitor
$17.95$18.89
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Tuya Solar Light Sensor IP65 Outdoor Brightness Detection Luminance7272
$32.89
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SALE Automatic Infrared PIR Motion Sensor Switch Auto On/Off Lamp Control Replace Kit
$10.23$10.77
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Ubiquiti Camera G4 Instant Cover UNIFI-G3-INSTANT-COVER - NEW SEALED
$55.99
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LED Outdoor 90~250V 180 Degree Infrared PIR Motion Sensor Detector Wall Light
$15.79
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220V Smart Automatic Barrier Opener Vehicle Loop Detector System
$31.79
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Mini PIR Infrared Motion Sensor Detector Switch LED Strip Automatic Switch Black
$13.59
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12V DC PIR Infrared Body Motion Sensor Automatic Detector Control Smart Switch
$18.99
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SALE 4 Modes Solar Motion Sensor Alarm 129dB Outdoor Siren With 13 Sounds For Farm
$25.46$26.80
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2 Sets Magnetic Reed Switch NO NC Wired Surface Mounted Magnetic Contact Switch
$14.79
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Nickel Plated Brass LJ12A3-4-J/EZ AC NO Inductive Proximity Sensor Switch Detec
$12.69
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9w Round 18LED Infrared Sensor Downlight Human Body Induction Recessed Ceiling
$21.19
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Adjustable Infrared IR Body Motion Sensor Switch Automatic Module Wall Mount
$14.19
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2 Pack Bunker Hill Security Vibration Window and Door Alarm Siren, Model 95054
$18.00
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SALE 110 dB Water Alarm w/Detachable Sensor for Hard-to- Areas BWD-HWA
$17.55$18.47
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Abode Home Security System Door Window Contact 104013. MAGNET NOT INCLUDED.
$19.99
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Honeywell Resideo RWD14 Water Alarm
$40.72
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180 Degree Motion Sensor for Security Floodlights White
$25.99
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Leviton OPP20-D1 Occupancy Sensor Power Pack (lot of 3)
$75.00
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SALE SimpliSafe Original Generation Door/Window Entry Sensor (ES1000) - NEW
$12.60$21.00
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PHILIPS LRM2340 OCCUPANCY SENSOR, FIXTURE MOUNT, HIGH BAY 360° PIR, 120V
$79.99
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B-Hyve Smart Flood Sensor 3-Pack with Wi-Fi Hub
$117.29
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Automatic Water Leak Detector with Sensors and Shut-off Valve
$74.88
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Handrail Bracket Stainless Steel Brackets Wall Support Easy Installation
$18.93
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Driveway Alarm, Home Security Alert System with 36 Melodies, Plug-In Receiver a
$36.67
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NIB Optex RCTD-10U Wireless 1000 TD-10U Sensor + RC-10U Receiver Set **2 Units**
$149.95
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Wireless Open/Close Sensor for Doors & Windows, 2843-222 Hub Required for Smarth
$75.99
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Wireless Door Alarm Remote Control for Home Security with 105 Decibel Sound
$23.99
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Wifi Water Leak Detector 3 Packs, Leak Alert with Remotely Email/App Push and So
$76.99
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Outdoor Waterproof Wired Motion Detector Dual PIR Sensor Pet Immunity Security
$44.79
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SALE 2 Ademco 4278EX-SN Multiplex Motion Sensor
$42.00$60.00
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Moose Products MPI-38 Self Contained Siren Security Speaker Alarm
$39.99
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Verkada SV21 Environmental Sensor CO2 Temp Humidity Wi-Fi Wireless Battery White
$500.00
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