Ademco Honeywell 4208U Universal 8-Zone Expander vplex v-plex (BRAND NEW sealed)
$55.00
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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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Honeywell Water Defense Alarm RWD41 Water Alarm Detection Home
$18.99
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8 Pcs AM312 Mini PIR Motion Sensor Module Pyroelectric Infrared Detector Set
$16.99
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New for the 1/2 Mile Driveway Alarm Wireless Sensor System Driveway Sensor
$60.86
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GE Portable Wire-Free EZSmart Motion Sensor Z Wave Plus Monitor W/mobile
$26.98
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12V 24V PIR Sensor LED Motion Sensor PIR Probe for LED Light Strip Black 2Pcs
$17.25
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Barracuda Pumps Wireless Remote Water Detector Reed Sensor For Sump Pumps- New!
$29.95
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6 PCS WIRELESS Home Window Door Burglar Security ALARM System Magnetic Sensor
$15.99
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10.525GHz Doppler Microwave Motion Sensor for Raspberry Pi & Arduino - 16m Range
$36.99
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Tailuxe Wireless LED Spotlight, Battery Operated Motion Sensor Outdoor Brown
$25.60
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SALE Smart WiFi Door Sensor - Wireless Alerts, Compatible with Alexa/Google - 4-Pack
$62.47$78.09
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Wireless Signal Hidden Camera Detector
$8.00
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Sensorswitch Ncm Pdt 9 Rjb Ceiling Mount Sensor, Occupancy, Digital Cat5 Cable,
$271.99
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CLOUDY BAY Motion Sensor Ceiling Light 6.5 inch-5000k day light, 5000K
$27.83
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SALE SimpliSafe ES3 Entry Door Window Sensor Magnetic White 3rd Generation New
$9.98$10.84
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Energy Converter, 5000W Modified Wave Transformer, 12V DC to 110V AC Vehicle Ada
$414.60
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Optex RCTD-10U Wireless 1000 TD-10U Sensor + RC-10U Receiver Set
$99.99
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Verkada SV23 Environmental Sensor, Wired Indoor, White (SV23-HW-R)
$799.00
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SimpliSafe Home Security System Keypad SSKP3 Simpli Safe Remote - Working -
$21.00
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Adjustable PIR Infrared Motion Sensor for Outdoor Lighting 110 Degree Range
$16.99
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Ring Mailbox Sensor, Up to 3 Years of Battery Life – Black BLACK
$26.00
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SALE 1980 Heathkit Assembly Manual Informer Ultrasonic Alarm Gd-49 (DOES NOT WORK)
$38.24$44.99
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Motion Sensor DC 5V 24V Light Switch Movement Detector Automatic PIR Sen E
$10.55
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5V-24V PIR Infrared Ray Motion Sensor Switch USB/DC LED Detector Switching
$11.51
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3-5m Automatic Body Infrared PIR Motion Sensor Detector Switch For LED light E
$10.55
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Automatic Door 24.125Ghz Microwave Motion Sensor,Autodoor Motion Tracking
$19.94
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New 10 x RC-33 NC Wired Door Contact Sensor Alarm Magnet Reed Switch 7-17mm
$13.33
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Htzsafe Solar Wireless Driveway Alarm System- 1/2 Mile Long Transmission Range-
$186.19
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Automatic Light Sensor Control Switch DC8-50V Photocell Light Switch Accessory
$12.85
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Ring Alarm Motion Detector, 90 Degree Coverage 25ft Range, NEW, 2nd Gen (4-Pack)
$77.99
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Infrared Motion Sensor Switch 140° Detection Angle AC100-240V for Public Places
$12.76
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AC 85-265V Professional Motion Infrared Sensor Switch For Outdoor 180° Detection
$12.76
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2 Pack Wireless Motion Detector Alarm - PIR Sensor for Pets, Dogs & Intruder Ale
$79.99
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Effective Device Water Leak Alarm Flood Level Overflow Detector Security
$10.74
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SimpliSafe WT3 Water Sensor Wireless Leak Detector Open Box
$23.99
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Freezer Door Alarm Battery Powered Compact Size with 3 Loud and Soft Modes
$29.97
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Door Window Sensors XHS2-TY , XHS2-UE Home Comcast Xfinity Security MCT-350
$16.88
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Indoor Motion Detector Alarm with Remote Control, 110dB Alert, 4 Volume Levels
$49.99
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SALE Lot of 4x LongJohn JL-404C Pencil Photocells (120-277V) Photo Cell Sensor Switch
$33.15$39.00
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Aqara Motion Sensor P1 Requires AQARA HUB 5-Year Battery Life Pack Of 3
$59.99
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GE Personal Security Motion Sensing 120 dB Alarm / Entry Chime w/ Remote 51207
$24.99
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SimpliSafe ES3 (5-Pack) Entry Door Window Sensor White 3rd Generation Brand New
$40.00
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Weatherproof Smart Driveway Alarm with Adjustable Detection and App Connectivity
$65.99
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Simplisafe Motion Sensor-Gen 3-White-New in Original Box
$17.00
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Simplisafe Motion Sensor-Gen 3-White-New in Original Box-Never Used
$24.95
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Temperature Sensor - Hot/Cold Detection - Compatible with Home Security System
$42.55
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1pair 100m Dual Beam IR Infrared Detector Module Burglar Alarm for Home Security
$37.69
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8 Pack Door Stop Alarm 120dB Security Wedge Stoppers for Home Travel Safety Tool
$53.99
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