Kini Safe Alert WiFi Motion Sensor Alarm RealTime App, SMS & Email Alerts G...
$285.37
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
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.
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
129dB Solar Motion Sensor Alarm 4 Modes Red Blue Flashing Lights For Outdoor
$24.83
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
Automatic Light Sensor Control Switch DC8-50V Photocell Light Switch Accessory
$12.32
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
New 10 x RC-33 NC Wired Door Contact Sensor Alarm Magnet Reed Switch 7-17mm
$12.78
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
12~24V Home Security One Beam Alarm Photoelectric Infrared Laser Sensor Detector
$15.08
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
2pcs PIR Motion Sensor Switch Wall Light Switch Fit 16mm Thread Diameter
$13.79
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
Automatic Door 24.125Ghz Microwave Motion Sensor,Autodoor Motion Tracking
$19.31
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
5-24V USB Port Detector Infrared PIR Motion Sensor Switch For Led Light Strip dd
$11.03
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
AC 85-265V Professional Motion Infrared Sensor Switch For Outdoor 180° Detection
$12.23
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
LINKCRO Septic Pump Alarm，Sump Pump Alarm with Pump Control Panel， High Water...
$144.59
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
SALE 30ft Range Zigbee Motion Sensor Set - Compatible with Alexa & SmartThings
$79.79$83.99
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
GE Indoor Security Audible Window/Door Alarms 2-Pack Sensor NEW
$20.00
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
SimpliSafe Original Generation (ES1000) Door/Window Entry Sensor - BRAND NEW
$5.00
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
5-Pack Wyze WHSK1 Sense Starter Kit Smart Home Motion & Entry Sensors White
$84.95
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
NO HARDWARE! Honeywell PROSIXGB PROSERIES GLASSBREAK DETECTOR 2 WAY WIRELESS
$34.99
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
Honeywell Home 5800MINI Wireless Door/Window Contact Sensor, White, Indoor
$50.00
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
SimpliSafe ES3 Entry Door Window Sensor White 3rd Generation Brand New LOT 2
$30.00
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
Honeywell Dual Tec DT-7435 Motion Sensor
$30.00
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
Vintage Honeywell Defender I Area Protection Alarm System Model CK100A1008-1
$9.94
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
SimpliSafe Water Sensor WT3 - Security System New Factory Sealed.
$35.00
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
NEWLEC NL5701B OCCUPANCY DETECTOR PIR SENSOR
$45.49
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
NEW - GE Indoor Window Door Battery Operated Audible Security Alarm Kit, 36017
$13.00
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
HONEYWELL 5828V 5828 VOICE WIRELESS LCD KEYPAD ADEMCO LYNX 5 7 TOUCH VISTA 20P N
$99.95
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
Visonic NEXT K9-85 Pet Tolerant Digital PIR
$10.00
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
mmWave Radar Motion Sensor Bracket Set - Multi-Person Detection, Fall Alerts, Ho
$179.99
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
Wyze Home Monitoring Security System Kit Sense Hub Keypad 2 Entry Motion Sensors
$60.00
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
Lakumu 9" Rechargeable Motion Sensor Ceiling Light with 9 Inch(1-Pack), White
$44.29
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
Rechargeable Motion Sensor Closet Light with Remote, 1 Pack, 3CCT-White
$36.24
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
5Pack Wired Door Contact Sensor NC Surface Mount Magnetic Reed Switch Brown
$14.30
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
OSIDEN Rechargeable Motion Sensor Ceiling Light Wireless Magnetic White
$29.34
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
Ring Contact Sensor 2nd Gen Riser New
$9.98
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
INSTEON Open/Close Sensor 2843-222
$19.99
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
SALE WATTSTOPPER CU-250-W ULTRASONIC VACANCY WALL SWITCH SENSOR, 600W, 120V, WHITE
$49.76$59.95
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
Latest Gen3 SimpliSafe Door Window Magnetic Entry Sensor Model ES3
$14.99
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
SALE NWB Battery Operated Wireless Driveway Alarm Alert Security System Bunker Hill
$13.99$28.99
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
SimpliSafe Entry Door/Window Sensor (ES1000) - Gen 1 - 2 Pack
$14.00
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
WINLAND WATERBUG #W-S-U WATER DETECTION SENSOR
$35.25
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
C by GE Wire-Free Motion Smart Sensor Battery Powered Motion Sensor,White ,BNIB
$19.00
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
Moen Flo by Moen Smart-Enabled Water Leak Sensor 920-004
$62.99
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
Philips 570977 Hue Motion Sensor - White
$61.95
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
SALE Aeotec Recessor for MultiSensor and TriSensor – Discreet in-Wall Mount for a ...
$20.97$29.96
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
Honeywell FG-1625F FlexGuard Glassbreak Detector
$19.99
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
Greengate Cooper Dual Tech Low Voltage Occupancy Sensor OAWC-DT-120W
$28.00
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
SALE AC180-240V 50/60Hz Auto On/Off Light Voice Sound Sensor Switch Time Delay G
$2.87$3.05
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
Set of 5 Water Leak Alarm for Smart Water Leak Sensor with 1 MCable Water Leak A
$13.50
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
Car AirConditioning Knob Ac Heat Control Switch Button for Focus 2 Focus 3 05-14
$13.07
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
SALE Waterproof LED Solar Alarm Warning Light Sensor Lamp Alert Remote Control M
$12.47$13.26
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.
SALE Automatic Sliding Door Opener Safety Beam Sensor Infrared Anti-Clip Device c
$22.28$23.71
View on eBay
Affiliate link — we may earn a commission, at no extra cost to you. Read our affiliate disclosure.