Samsung SmartThings ADT Door and Window Detector
$9.77
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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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Hanna Mail Chime Wireless Mailbox Alert Model 1200 Alarm Theft Deterrent New
$39.99
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HUBBELL WIRING DEVICE-KELLEMS AD2000I1 Motion Snsr,PIR/Usonic,120-277V AC,Ivory
$378.97
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SALE Water Leak Starter Kit: Hub + 4 Leak Sensor 1 Silent, LoRa Long-Range, App/SM...
$87.99$109.99
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SALE Alarm Contact Sensor 6-Pack - 2nd Gen | Monitor 6 Doors or Windows | Instant ...
$143.99$179.99
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BLUE By ADT Wireless Door & Window Sensor Model# SSH1R0-29 NEW
$14.95
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StroneSecurity System Motion Sensor Alarm 120 dB MA795 NIP
$24.99
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SENSOR SWITCH NCM PDT 9 RJB Occ Snsr,PIR/Mphonic,24V AC/DC,475sqft 23J491
$334.16
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Evolve 360 degree Wireless Z-Wave Motion Detector Occupancy Sensor PIR-200-EVOLV
$89.99
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SALE DSC SD 15W-ULF 15W Dual Tone Surface Mount Electronic Siren
$12.99$19.99
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SALE AC100-240V Motion Sensor Switch PIR Infrared Auto On/Off for LED Lights White
$15.03$15.99
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Dimango RC2215 Wireless Security Door Alarm with built in battery backup
$24.99
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NEW Sealed Kangaroo A0004 Water Leak Detector WiFi Home Security System
$24.95
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Water Leak Detector, 1/4 Mile World's Longest Range, Wireless Smart Water Lea...
$29.49
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Streetwise Motion Activated Alarm and Chime. Security Product
$14.95
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YoLink Water Leak Detector, 1/4 Mile World's Longest Range, Wireless Smart Water
$23.99
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ADI PRO Magnetic Contact Roller Ball/Plunger 0E-ROPLUNGE White (10 pcs)
$25.00
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Monoprice Z-Wave Plus Door/Window Sensor Wireless Indoor White 15270
$20.00
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SALE Defiant 270 Degree White Replacement Outdoor Motion Sensor New in Box
$20.79$25.99
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Lot of 4 Honeywell / Resideo RWD21 Reusable Water Leak Alarms - Used
$29.99
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driveway alarm wireless outside motion sensor
$19.99
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10 Sets NC Wired Surface Mounted Alarm Magnetic Door Contact Sensor Door Window
$26.01
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10 Sets Magnetic Reed Switch MC-31 NC Surface Mount Wired Security Window Door C
$23.41
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Honeywell Home 5815 Wireless Door/Window Transmitter Sensor, White Battery
$20.00
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Honeywell Home 5800MINI Wireless Door/Window Contact Sensor, White (Lot of 2)
$40.00
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Resideo RF6CT Wireless Door Window Security Sensors w/ Magnets & Mounts Lot 16
$80.00
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Upgraded Smart Water Leak Detector 1S with 1804 Ft Ultra-Long Range, Wifi Water
$98.99
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DSC LC-100PI Digital PIR Detector With Pet Immunity Motion Sensor
$15.00
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Presence Sensor FP2, Mmwave Radar Wired Smart Motion Sensor, Zone Positioning, M
$149.99
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360° Radar Detector 1000 Ft Range K KA1 & K2 Band Brand New By Gadget Gear
$19.95
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SALE Long Range Wireless Driveway Alarm - Weather Resistant
$56.24$74.99
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Leviton Osc10-M0w Occ Snsr, Pir/Usonic, 24V Dc, 1, 000 Sq Ft
$136.99
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ADT Self Setup Motion Sensor - White (SSM1R0-29-S) “Minor Box Damage”
$21.99
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Hidden Camera Detector & Bug Detector - Hidden Devices Detector for Hidden.New
$37.95
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Google Nest Detect Sensor H1100WES White Door Window Motion Sensor Sealed
$22.98
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SALE Reed Switch NC for Home Security - 10mm Distance
$46.49$61.99
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SALE Advanced Wireless Motion Detector with Solar Power - Weatherproof & Customizable
$94.20$117.75
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Linear Hondwa01 Door / Window Wireless Sensor Compatible with Honeywell
$15.99
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Leviton Ods15-Idi Occ Snsr, Pir, 120-277V Ac, Ivory
$65.89
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Leviton Ods10-Idi Occ Snsr, Pir, 120-277V Ac, Ivory
$68.29
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Leviton Ossmt-Gdi Occ Snsr, Pir/Usonic, 120-277V Ac, Ivory
$98.25
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Leviton Oswlr-I0w Occ Snsr, Pir, 24V Dc, 1, 400 Sq Ft
$110.99
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Leviton Acs10-Dmw Ceiling Mount Sensor, Occupancy, Vacancy, Wireless, White,
$198.99
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Leviton Odd24-Idw Occ Snsr, Pir, 120/230/277V Ac, Wht
$81.69
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New - Flume Smart Leak Detector & Water Flow Monitor - Buy Here For Less, Save $
$99.99
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Detection Systems (now Bosch) DS415i Single Beam Photoelectric Intrusion Sensors
$49.00
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Lot of 10 BLUE By ADT Door And Window Sensors Brand New
$79.97
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Lot of 3 blue by ADT Door & Window Sensors SSH1R0-29 Brand New
$39.97
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