Plug and Safe Mobile Intruder Detector Alarm Model PS10, Home RV Camper Hotel +
$10.00
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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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Automatic Water Leak Detector w/ Sensors & Stut-off Valve Water Leak Detecting
$69.81
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Easy-Mount 90 dB Door & Window Alarm - Ultimate Safety for Children & Home
$19.99
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RC-33 NC Recessed Magnetic Door Switch Security Sensor - 5 Sets, White
$16.99
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Recessed Wired Security Window/Door Contact Sensor, NC Magnetic Reed Switch, 2PC
$12.99
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Alarm Siren DCS Model SD 20WS Single Tone Home Security Protection Alert
$15.76
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Vintage RadioShack Invisible-Beam Entry Alert 49-312 Home Business Alarm NIB
$8.00
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SALE Zircon Leak Alert Water Leak Detector Flood Sensor Alarm Set Of 3 Untested
$23.74$24.99
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SALE Wireless Door Window Protection Sensors - Pack of 4//
$115.19$191.99
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SALE MOTION SENSOR WITH BATTERIES POWERED BY WIZ (1-PACK)
$13.50$30.00
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SALE 1pcs New SENSE-WARE UV/IR detector T-229/4P
$2,471.94$2,658.00
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Long Range Wireless Driveway Alarm - 1/2 Mile Motion Sensor Security System Kit
$123.99
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Nomo Smart Care Essential Care Kit 1001R-01 - Open Box
$119.99
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SALE 120dB Door Window Alarm, Home Security Chime
$45.59$56.99
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Bunker Hill 60498 Security36 Led Solar Motion Detector Light (New In Box)
$20.00
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Compact NC Magnetic Contacts for Door Security - 5 Pack with Concealed Hardware
$17.99
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Eve Door & Window Wireless Contact Sensor Works With Apple Home
$19.99
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BIBENE 2.4Ghz WiFi Alarm System Wireless with APP Push Notification Security
$24.99
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SALE Commercial/Residential Motion Sensor
$39.59$65.99
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Vivint VS-DW2100-345 6 Wireless Recessed Door Sensors Smart Home
$90.00
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1/2PCS Ultrasonic Solar Sound Light Alarm Animal Repeller Dog Squirrel Raccoon
$31.39
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SALE 315mhz Infrared Motion Sensor Home Garage Alert Security System
$18.24$21.21
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129dB Solar Motion Sensor Alarm Outdoor Dog Barking Security Siren with Remote
$31.39
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SALE Universal USB Port Detector PIR Motion Sensor Switch For Led Light Strip
$10.74$12.35
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SALE Smart Thermometer Hygrometer Wi-Fi Temperature Humidity Sensor For Alexa/Google
$19.17$22.03
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SALE Simple Water Leak Alarm Flood Level Overflow Detector Sensor Home Security
$10.03$11.53
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Recessed Magnetic Reed Switch NC for Door/Window Alarm - Set of 3
$9.99
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X-10 RoboDog Barking Dog Alarm Model SD20A
$39.99
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Solar Wireless Driveway Alarm System, 1/2 Mile Range, IP65 Weatherproof, 120dB
$75.71
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SALE Black 24.125GHz Human Inductive Motion Microwave Radar Sensor For Automatic Door
$14.00$20.00
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TECKNET Solar Wireless Driveway Alarm with 2600FT Long Range & 36 Melodies & 5 V
$35.00
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SALE HOMSECUR Wireless PIR Motion Detector Human Body Infrared 433MHz Home Security
$44.07$46.39
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SALE Reliable Solar Driveway Alarm System: Wireless, Weatherproof & Easy to Install
$37.95$40.61
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5 Sets RC-33 NC Magnetic Door Switch Security Contact Sensor Alarm - White
$16.99
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Automatic Water Leak Detector with Sensors and Shut-off Valve
$74.67
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SALE Qolsys QS1231-840 IQ Wireless PIR Motion Sensor, Interlogix Compatible———-19
$32.49$49.99
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Simplisafe Keypad Wall Mount, Door Sensor, Base Station Gen 3 Wireless
$39.95
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MC-33C Recessed Magnetic Door/Window Contact Sensor Alarm - 2 Sets
$15.99
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Recessed Door Sensor for Monitoring Open/Closed Status with HomeKit & Alexa
$51.99
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5-Pack Recessed Wired Security Magnetic Door Window Contact Sensor Alarm
$18.99
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KERUI Driveway Alarm Wireless System Outdoor Motion Sensor for Home Security USA
$37.99
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PIR Motion Sensor Light Switch, No Neutral/Ground, 120V, 150W LED/CFL, 2-Pack
$95.99
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Automatic Water Leak Detector with Sensors and Shut-off Valve
$78.60
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Motion Sensor Switch with LED Guide Light, 1200 Sq Ft Coverage, No Neutral, Adju
$59.99
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KERUI Driveway Alarm Wireless System Outdoor Motion Sensor for Home Security USA
$36.99
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3 Sets White Iron Door Recessed Wired Security Contact Sensor Alarm
$15.99
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Wired Magnetic Door Window Contact Sensor Set for Home Security, White
$15.99
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SALE 4pcs Zigbee Window Door Sensors Smart Contact Sensors For App Home Assistant
$24.59$25.88
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