Skip to main content
Hi !Hi! Sign in or registerDaily DealsBrand OutletGift CardsHelp & Contact
Sell
Watchlist
My eBay
  • Summary
  • Recently Viewed
  • Bids/Offers
  • Watchlist
  • Purchase History
  • Buy Again
  • Selling
  • Saved Feed
  • Saved Searches
  • Saved Sellers
  • My Garage
  • Sizes
  • My Collection
  • Messages
  • PSA Vault
Please sign-in to view notifications.
Loading...
eBay Home
Advanced
Copyright © 1995-2025 eBay Inc. All Rights Reserved. Accessibility, User Agreement, Privacy, Consumer Health Data, Payments Terms of Use, Cookies, CA Privacy Notice, Your Privacy Choices and AdChoice

System Sensor Home Security

Best selling

See All
  • Ring 4SS1S8-0EN0 Alarm Smoke & CO Listener

    Ring 4SS1S8-0EN0 Alarm Smoke & CO Listener

    (16)
    $22.99 New
    $17.99 Used
  • System Sensor CO1224T Carbon Monoxide Detector

    System Sensor CO1224T Carbon Monoxide Detector

    (7)
    $49.99 New
    $20.00 Used
  • System Sensor 2WTA-B I3 Series Smoke Detector

    System Sensor 2WTA-B I3 Series Smoke Detector

    (6)
    $50.00 New
    $20.24 Used
  • Ring 4SC2S9-0EN0 Alarm Smoke & CO Listener - 2 Count

    Ring 4SC2S9-0EN0 Alarm Smoke & CO Listener - 2 Count

    (3)
    $50.01 New
  • System Sensor CO1224TR Carbon Monoxide Detector - White

    System Sensor CO1224TR Carbon Monoxide Detector - White

    $65.00 New
    $28.00 Used
  • System Sensor RTS451KEY Fire Alarm Remote Test Station

    System Sensor RTS451KEY Fire Alarm Remote Test Station

    (1)
    $50.00 New
    $16.99 Used
  • System Sensor 2W-B i3 Series 2-Wire Photoelectric Smoke Detector

    System Sensor 2W-B i3 Series 2-Wire Photoelectric Smoke Detector

    (9)
    $78.47 New
    $19.99 Used

Related Searches

  • Home Security System
  • Home Security System Wireless
  • Home Security System Wired
  • Security Alarm System
  • Home Alarm System
  • Home Security Wireless
  • Safe Home Security
  • House Alarm System
  • House Alarm System Wifi
  • Home Alarm System with Camera
  • Smart Home Alarm System
  • Home Surveillance System Wireless

breadcrumb

  • eBay
    • Home & Garden
    • Home Improvement
  • Home & Garden
  • Home Improvement
  • Home Security
  • System Sensor Home Security

Review highlights

Recommended by our customers

  • Great product that fits an important niche.

    By chrisv1

    The listener easily connects CO/Smoke detectors to the Ring security system. My house has hardwired power to smoke dete... see all reviews

    Verified Purchase

    Ring Alarm smoke &CO Listener - Brand new

Shop by category

  • Home Improvement
    • Home Security
    • Alarm Systems
    • Door & Window Sensors
    • Door Entry Systems & Intercoms
    • Dummy Bell Boxes
    • Fire Escape Ladders
    • Glass Break Detectors
    • Home Security Parts
    • Key Blanks
    • Key Fobs
    • Key Safes, Boxes & Hideaways
    • Other Home Security
    • Padlocks
    • Personal Alarms
    • Remotes & Wireless Transmitters
    • Safes
    • Security Bars & Grills
    • Security Keypads
    • Security Signs & Decals
    • Security Timers
    • Sirens
    • Smoke & Gas Detectors
    • Wall Spikes & Barbed Wire
    • Water & Temperature Detectors
  • All Listings
  • Auction
  • Buy It Now
  • Best Offer
  • Best Match
  • Time: ending soonest
  • Time: newly listed
  • Price + Shipping: lowest first
  • Price + Shipping: highest first
  • Distance: nearest first
  • List View
  • Gallery View

228 results

Sort: Best Match

  • Best Match
  • Time: ending soonest
  • Time: newly listed
  • Price + Shipping: lowest first
  • Price + Shipping: highest first
  • Distance: nearest first
  • Brand: System Sensor- Selected

    • Ring Smoke/CO Listener for Ring Alarm - Image 1 of 2
    • Ring Smoke/CO Listener for Ring Alarm - Image 2 of 2

    Ring Smoke/CO Listener for Ring Alarm

    Brand New · System Sensor
    (16)
    $22.99
    Free shipping
    131 sold
    S⁣6⁣K⁣ ⁣p⁣Y⁣T⁣ ⁣о⁣2⁣n⁣s⁣o⁣7⁣r⁣e⁣d⁣ ⁣4⁣O⁣ ⁣O⁣7⁣ ⁣⁣H⁣⁣⁣
    • 5-in-1 Plug in Gas & Smoke & Carbon Monoxide Detector, Combination CO Alarm with - Image 1 of 3
    • 5-in-1 Plug in Gas & Smoke & Carbon Monoxide Detector, Combination CO Alarm with - Image 2 of 3
    • 5-in-1 Plug in Gas & Smoke & Carbon Monoxide Detector, Combination CO Alarm with - Image 3 of 3

    5-in-1 Plug in Gas & Smoke & Carbon Monoxide Detector, Combination CO Alarm with

    Open Box · System Sensor
    $24.95
    or Best Offer
    $6.36 shipping
    2 watching
    P⁣S⁣E⁣р⁣o⁣n⁣s⁣o⁣r⁣e⁣d⁣ ⁣S⁣⁣⁣T⁣⁣⁣⁣⁣⁣ ⁣⁣⁣⁣2⁣⁣⁣
    • System Sensor CO1224T Carbon Monoxide Detector 4 Wire FAST FREE SHIPPING a - Image 1 of 4
    • System Sensor CO1224T Carbon Monoxide Detector 4 Wire FAST FREE SHIPPING a - Image 2 of 4
    • System Sensor CO1224T Carbon Monoxide Detector 4 Wire FAST FREE SHIPPING a - Image 3 of 4
    • System Sensor CO1224T Carbon Monoxide Detector 4 Wire FAST FREE SHIPPING a - Image 4 of 4

    System Sensor CO1224T Carbon Monoxide Detector 4 Wire FAST FREE SHIPPING a

    Open Box · System Sensor
    (7)
    $51.88
    Free shipping
    3⁣7⁣S⁣ ⁣р⁣o⁣I⁣6⁣ ⁣G⁣n⁣J⁣s⁣o⁣ ⁣Z⁣r⁣V⁣ ⁣e⁣d⁣⁣⁣G⁣A⁣⁣⁣⁣
    • System Sensor 2WTA-B Photoelectric i3 Series Smoke Detector 2 Wire New Open Box - Image 1 of 3
    • System Sensor 2WTA-B Photoelectric i3 Series Smoke Detector 2 Wire New Open Box - Image 2 of 3
    • System Sensor 2WTA-B Photoelectric i3 Series Smoke Detector 2 Wire New Open Box - Image 3 of 3

    System Sensor 2WTA-B Photoelectric i3 Series Smoke Detector 2 Wire New Open Box

    Brand New · System Sensor
    (6)
    $54.40
    Was: $64.00was - US $64.00
    Free shipping
    9⁣8⁣ ⁣S⁣S⁣p⁣o⁣n⁣T⁣s⁣o⁣ ⁣r⁣9⁣I⁣е⁣ ⁣N⁣d⁣⁣⁣Y⁣ ⁣F⁣J⁣ ⁣⁣⁣
  • New Open BOX Ring Smoke/CO Listener for Ring Alarm - Image 1 of 3

    New Open BOX Ring Smoke/CO Listener for Ring Alarm

    Open Box · System Sensor
    (16)
    $15.72
    Was: $17.86was - US $17.86
    Free shipping
    136 sold
    B⁣4⁣⁣ ⁣⁣G⁣⁣⁣⁣R⁣ ⁣⁣⁣⁣N⁣9⁣⁣⁣⁣ ⁣⁣⁣⁣Z⁣⁣⁣⁣⁣
  • System Sensor 2WTA-B Photoelectric Smoke Detector - Same Day Shipping (SEALED) - Image 1 of 4

    System Sensor 2WTA-B Photoelectric Smoke Detector - Same Day Shipping (SEALED)

    Brand New · System Sensor
    (6)
    $59.10
    or Best Offer
    $7.84 shipping
    149 sold
    A⁣⁣⁣⁣7⁣⁣ ⁣⁣⁣⁣⁣⁣⁣⁣⁣Z⁣9⁣⁣ ⁣F⁣6⁣ ⁣⁣O⁣8⁣⁣ ⁣R⁣
  • Ring Smoke/CO Listener Detector for Ring Alarm Home Security Systems - Image 1 of 3

    Ring Smoke/CO Listener Detector for Ring Alarm Home Security Systems

    Open Box · System Sensor
    (16)
    $19.99
    or Best Offer
    Free shipping
    ⁣J⁣⁣⁣⁣1⁣⁣⁣ ⁣⁣⁣⁣9⁣⁣4⁣ ⁣⁣O⁣⁣7⁣⁣ ⁣0⁣⁣⁣M⁣ ⁣3⁣
  • 2 Wire I4 Interface Module, System Sensor #COSMOD2W - Image 1 of 1

    2 Wire I4 Interface Module, System Sensor #COSMOD2W

    Brand New · System Sensor
    $64.75
    Free shipping
    R⁣2⁣ ⁣0⁣7⁣⁣ ⁣⁣G⁣⁣H⁣⁣⁣ ⁣C⁣⁣⁣Z⁣ ⁣⁣B⁣J⁣ ⁣P⁣⁣ ⁣⁣⁣
  • NEW System Sensor C01224T Carbon Monoxide Detector - Image 1 of 1

    NEW System Sensor C01224T Carbon Monoxide Detector

    Brand New · System Sensor
    $47.99
    or Best Offer
    Free shipping
    Only 1 left!
    ⁣⁣X⁣⁣R⁣⁣⁣⁣⁣ ⁣⁣⁣⁣⁣⁣⁣2⁣⁣⁣⁣S⁣⁣⁣⁣⁣ ⁣P⁣⁣
  • System Sensor COSMO-2W Combination Carbon Monoxide and Smoke Detector - Image 1 of 4

    System Sensor COSMO-2W Combination Carbon Monoxide and Smoke Detector

    Pre-Owned · System Sensor
    $39.99
    $7.50 shipping
    6⁣⁣⁣⁣L⁣ ⁣I⁣⁣O⁣⁣ ⁣⁣O⁣⁣⁣⁣T⁣⁣⁣⁣⁣ ⁣⁣9⁣6⁣⁣⁣ ⁣
  • System Sensor, 12/24 V, Photo, Relay, Heat, 4-Wire, SS Model #4WTR-B. - Image 1 of 1

    System Sensor, 12/24 V, Photo, Relay, Heat, 4-Wire, SS Model #4WTR-B.

    Brand New · System Sensor
    $77.95
    Free shipping
    G⁣⁣⁣R⁣⁣ ⁣B⁣C⁣ ⁣⁣⁣⁣Z⁣⁣⁣L⁣ ⁣⁣⁣Y⁣6⁣ ⁣C⁣⁣⁣O⁣ ⁣E⁣
  • Replacement CO Cell for the I4 Series Detectors, System Sensor #CO-REPL - Image 1 of 1

    Replacement CO Cell for the I4 Series Detectors, System Sensor #CO-REPL

    Brand New · System Sensor
    $49.95
    Free shipping
    ⁣L⁣⁣T⁣ ⁣K⁣⁣⁣C⁣ ⁣A⁣⁣⁣A⁣ ⁣1⁣⁣⁣⁣U⁣⁣⁣⁣ ⁣⁣Z⁣⁣⁣
  • 2x 5-in-1 Plug in Gas & Smoke & Carbon Monoxide Detector, Combination CO Alarm - Image 1 of 4

    2x 5-in-1 Plug in Gas & Smoke & Carbon Monoxide Detector, Combination CO Alarm

    Brand New · System Sensor
    $39.98
    Free shipping
    8⁣C⁣⁣⁣ ⁣X⁣⁣2⁣ ⁣⁣⁣Q⁣⁣⁣F⁣⁣ ⁣⁣6⁣⁣1⁣⁣⁣ ⁣⁣⁣S⁣C⁣
  • System Sensor CO1224TR Round, 12/24V, 4-Wire, System-Monitored Carbon Monoxide - Image 1 of 2

    System Sensor CO1224TR Round, 12/24V, 4-Wire, System-Monitored Carbon Monoxide

    Brand New · System Sensor
    $58.00
    or Best Offer
    $8.71 shipping
    Only 1 left!
    Ѕ⁣p⁣Z⁣9⁣o⁣n⁣ ⁣4⁣s⁣o⁣r⁣N⁣ ⁣e⁣d⁣⁣P⁣⁣⁣G⁣⁣ ⁣C⁣T⁣ ⁣⁣X⁣⁣
  • model 6000 Low Level Carbon Monoxide Monitor - Image 1 of 2

    model 6000 Low Level Carbon Monoxide Monitor

    Brand New · System Sensor
    $120.00
    or Best Offer
    $7.10 shipping
    S⁣A⁣E⁣ ⁣S⁣S⁣ ⁣p⁣o⁣W⁣n⁣Y⁣ ⁣s⁣о⁣T⁣V⁣ ⁣5⁣r⁣e⁣d⁣9⁣ ⁣⁣⁣⁣9⁣
  • Smoke Detector2412 Smoke Detector - Image 1 of 4

    Smoke Detector2412 Smoke Detector

    Open Box · System Sensor
    $45.00
    or Best Offer
    $8.71 shipping
    2⁣Ѕ⁣p⁣4⁣ ⁣K⁣o⁣6⁣n⁣ ⁣M⁣V⁣ ⁣s⁣o⁣r⁣e⁣d⁣2⁣D⁣⁣⁣ ⁣⁣⁣⁣6⁣⁣
  • System Sensor CO1224T Carbon Monoxide Detector with Sounder New - Image 1 of 4

    System Sensor CO1224T Carbon Monoxide Detector with Sounder New

    Brand New · System Sensor
    (7)
    $59.95
    Free shipping
    T⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣6⁣ ⁣⁣⁣⁣9⁣M⁣ ⁣⁣N⁣⁣G⁣⁣⁣⁣ ⁣⁣⁣
  • Ring Smoke/CO Listener for Ring Alarm ~ Brand New Open Box - Image 1 of 4

    Ring Smoke/CO Listener for Ring Alarm ~ Brand New Open Box

    Open Box · System Sensor
    (16)
    $19.99
    or Best Offer
    $5.19 shipping
    ⁣⁣Q⁣⁣R⁣⁣ ⁣7⁣⁣W⁣⁣⁣⁣ ⁣⁣⁣I⁣⁣D⁣ ⁣⁣⁣N⁣N⁣⁣ ⁣7⁣⁣
  • System Sensor COSMO-2W Combination Carbon Monoxide and Smoke Detector - Image 1 of 4

    System Sensor COSMO-2W Combination Carbon Monoxide and Smoke Detector

    Pre-Owned · System Sensor
    $29.99
    $7.50 shipping
    ⁣W⁣⁣⁣O⁣ ⁣⁣⁣⁣1⁣⁣1⁣⁣⁣ ⁣4⁣⁣⁣C⁣⁣ ⁣⁣⁣E⁣⁣⁣⁣⁣
  • system sensor direct wire smoke alsrm 2100AT - Image 1 of 3

    system sensor direct wire smoke alsrm 2100AT

    Brand New · System Sensor
    $42.50
    Was: $50.00was - US $50.00
    or Best Offer
    $8.24 shipping
    ⁣⁣K⁣T⁣⁣⁣⁣⁣⁣⁣⁣ ⁣⁣⁣V⁣⁣U⁣ ⁣J⁣⁣G⁣ ⁣K⁣I⁣⁣⁣⁣ ⁣
  • 4 Wire I4 CO/Smoke Detector, 8.5 to 35 VDC, System Sensor #COSMO-4W - Image 1 of 1

    4 Wire I4 CO/Smoke Detector, 8.5 to 35 VDC, System Sensor #COSMO-4W

    Brand New · System Sensor
    $113.95
    Free shipping
    6⁣⁣3⁣ ⁣⁣0⁣⁣T⁣ ⁣G⁣⁣D⁣⁣⁣⁣⁣⁣ ⁣X⁣⁣8⁣⁣ ⁣M⁣M⁣ ⁣H⁣⁣
  • Ring Smoke/CO Listener for Ring Alarm, New & Sealed - Image 1 of 4

    Ring Smoke/CO Listener for Ring Alarm, New & Sealed

    Brand New · System Sensor
    (16)
    $20.00
    Trending at $22.99

    eBay determines this price through a machine learned model of the product's sale prices within the last 90 days.

    $5.00 shipping
    ⁣B⁣E⁣ ⁣C⁣⁣Y⁣ ⁣⁣⁣⁣Y⁣Y⁣ ⁣J⁣⁣⁣⁣⁣I⁣ ⁣6⁣3⁣ ⁣⁣K⁣⁣⁣
  • System Sensor CO1224T With Realtest Technology Ul Listed Carbon Monoxide White - Image 1 of 3

    System Sensor CO1224T With Realtest Technology Ul Listed Carbon Monoxide White

    Brand New · System Sensor
    (7)
    $74.95
    or Best Offer
    Free shipping
    Only 1 left!
    ⁣Q⁣⁣⁣⁣O⁣⁣ ⁣6⁣⁣⁣⁣⁣⁣⁣⁣L⁣⁣⁣⁣ ⁣⁣3⁣⁣⁣⁣I⁣⁣
  • Smoke detector, 12/24 Volt, Photo, Thermal, 4-Wire, System Sensor #4WT-B - Image 1 of 1

    Smoke detector, 12/24 Volt, Photo, Thermal, 4-Wire, System Sensor #4WT-B

    Brand New · System Sensor
    $73.75
    Free shipping
    Q⁣S⁣⁣⁣ ⁣8⁣8⁣ ⁣F⁣⁣⁣⁣C⁣⁣ ⁣⁣⁣M⁣Q⁣ ⁣⁣⁣⁣⁣⁣⁣G⁣⁣
  • System Sensor CO1224T Carbon Monoxide Detector 4 Wire New-Old Stock - Image 1 of 4

    System Sensor CO1224T Carbon Monoxide Detector 4 Wire New-Old Stock

    Open Box · System Sensor
    (7)
    $53.32
    Was: $62.00was - US $62.00
    or Best Offer
    Free shipping
    J⁣⁣M⁣⁣⁣⁣ ⁣N⁣⁣F⁣ ⁣N⁣V⁣⁣ ⁣⁣⁣⁣⁣⁣⁣⁣B⁣1⁣ ⁣⁣J⁣0⁣
  • System Sensor 2WTA-B i3 Series 2-wire Photoelectric Smoke Detector w/Sounder - Image 1 of 4

    System Sensor 2WTA-B i3 Series 2-wire Photoelectric Smoke Detector w/Sounder

    Brand New · System Sensor
    (6)
    $69.95
    Free shipping
    F⁣C⁣ ⁣E⁣⁣⁣⁣⁣0⁣⁣ ⁣0⁣H⁣ ⁣⁣P⁣⁣⁣⁣9⁣ ⁣⁣C⁣⁣F⁣⁣ ⁣⁣
  • System Sensor 5621 135 Degree Fixed Temp / Rate-Of-Rise Dual Heat Detector - Image 1 of 2

    System Sensor 5621 135 Degree Fixed Temp / Rate-Of-Rise Dual Heat Detector

    Brand New · System Sensor
    $46.99
    Free shipping
    ⁣⁣6⁣⁣⁣H⁣ ⁣4⁣⁣⁣⁣B⁣ ⁣⁣⁣⁣6⁣⁣L⁣⁣⁣⁣⁣⁣ ⁣Z⁣⁣⁣
  • Ring Smoke CO Listener for Ring Alarm Brand New Factory Sealed - 2 Pack - NEW - Image 1 of 4

    Ring Smoke CO Listener for Ring Alarm Brand New Factory Sealed - 2 Pack - NEW

    Brand New · System Sensor
    (16)
    $49.99
    $7.99 shipping
    7⁣8⁣ ⁣4⁣⁣⁣4⁣⁣ ⁣⁣⁣6⁣H⁣⁣⁣⁣⁣ ⁣⁣⁣⁣⁣⁣⁣S⁣R⁣ ⁣H⁣
  • P2WLED-P SYSTEM SENSOR - Image 1 of 1

    P2WLED-P SYSTEM SENSOR

    ONE YEAR WARRANTY FROM FIRESAFETY2014!
    Brand New · System Sensor
    $74.50
    or Best Offer
    Free shipping
    6⁣S⁣p⁣о⁣n⁣W⁣s⁣ ⁣L⁣o⁣r⁣e⁣U⁣ ⁣d⁣⁣⁣4⁣⁣⁣⁣⁣G⁣⁣⁣⁣ ⁣⁣
  • YORK INTERNATIONAL SMOKE DETECTOR KIT / SM-501-P FOR MODEL# 2SD04701724 - Image 1 of 4

    YORK INTERNATIONAL SMOKE DETECTOR KIT / SM-501-P FOR MODEL# 2SD04701724

    Open Box · System Sensor
    $499.99
    or Best Offer
    $29.15 shipping
    S⁣p⁣o⁣n⁣T⁣s⁣o⁣r⁣е⁣I⁣ ⁣d⁣6⁣⁣⁣9⁣⁣⁣ ⁣X⁣⁣⁣D⁣ ⁣⁣⁣⁣H⁣
  • carbon monoxide detector/ System Sensor/For Hardwire Alarm / Fire System 4 Wire - Image 1 of 1

    carbon monoxide detector/ System Sensor/For Hardwire Alarm / Fire System 4 Wire

    Brand New · System Sensor
    $55.00
    Free shipping
    A⁣I⁣S⁣ ⁣Z⁣P⁣p⁣ ⁣o⁣V⁣H⁣ ⁣O⁣W⁣ ⁣K⁣N⁣n⁣s⁣o⁣ ⁣I⁣r⁣е⁣d⁣⁣⁣⁣
  • Smart Wifi Smoke Detector Sensor 80DB Alarm Fire Smoke Detector Fire Protection - Image 1 of 4

    Smart Wifi Smoke Detector Sensor 80DB Alarm Fire Smoke Detector Fire Protection

    Brand New · System Sensor
    $30.55 to $125.10
    Was: $59.83was - US $59.83
    Free shipping
    Ѕ⁣U⁣L⁣ ⁣p⁣o⁣G⁣n⁣s⁣o⁣r⁣4⁣e⁣ ⁣d⁣⁣J⁣C⁣⁣⁣ ⁣⁣S⁣R⁣ ⁣T⁣U⁣⁣
  • New Open Box One Ring Z-Wave Smoke / CO Listener for Ring Alarm - Image 1 of 4

    New Open Box One Ring Z-Wave Smoke / CO Listener for Ring Alarm

    Brand New · System Sensor
    (16)
    $14.99
    Trending at $22.99

    eBay determines this price through a machine learned model of the product's sale prices within the last 90 days.

    $5.51 shipping
    T⁣C⁣⁣⁣⁣⁣⁣⁣ ⁣⁣C⁣A⁣⁣ ⁣⁣⁣⁣O⁣W⁣⁣⁣⁣ ⁣0⁣⁣4⁣⁣⁣
  • Replacement CO Cell for the I4 Series Detectors, System Sensor #CO-REPL - Image 1 of 3

    Replacement CO Cell for the I4 Series Detectors, System Sensor #CO-REPL

    Brand New · System Sensor
    $49.95
    or Best Offer
    Free shipping
    Only 1 left!
    ⁣⁣D⁣G⁣ ⁣⁣S⁣H⁣ ⁣⁣5⁣⁣P⁣ ⁣R⁣R⁣⁣⁣⁣ ⁣⁣O⁣⁣⁣2⁣⁣ ⁣G⁣
  • NEW SYSTEM SENSOR CO1224TR CO2 CARBON MONOXIDE DETECTOR GOOD THRU 02/2035 - Image 1 of 1

    NEW SYSTEM SENSOR CO1224TR CO2 CARBON MONOXIDE DETECTOR GOOD THRU 02/2035

    Brand New · System Sensor
    $65.00
    Free shipping
    O⁣⁣⁣⁣K⁣ ⁣Q⁣⁣⁣0⁣⁣⁣ ⁣⁣J⁣⁣7⁣⁣ ⁣U⁣⁣⁣1⁣ ⁣⁣0⁣1⁣⁣
  • System Sensor CO1224T With Realtest Technology Ul Listed Carbon Monoxide White - Image 1 of 3

    System Sensor CO1224T With Realtest Technology Ul Listed Carbon Monoxide White

    Open Box · System Sensor
    (7)
    $69.99
    or Best Offer
    Free shipping
    K⁣B⁣⁣⁣⁣ ⁣X⁣⁣M⁣ ⁣⁣Q⁣⁣⁣⁣3⁣ ⁣A⁣9⁣⁣ ⁣7⁣T⁣⁣⁣⁣⁣ ⁣
  • System Sensor 2WTA-B Photoelectric Smoke Detector NEW IN BOX - Image 1 of 4

    System Sensor 2WTA-B Photoelectric Smoke Detector NEW IN BOX

    Brand New · System Sensor
    (6)
    $50.00
    or Best Offer
    Trending at $54.40

    eBay determines this price through a machine learned model of the product's sale prices within the last 90 days.

    Free shipping
    ⁣⁣⁣⁣D⁣⁣W⁣ ⁣⁣⁣⁣E⁣⁣0⁣⁣ ⁣8⁣⁣⁣Q⁣⁣ ⁣F⁣⁣0⁣⁣⁣ ⁣
  • Smoke detector, 12/24 Volt, Photo, Relay, Heat, 4-Wire, System Sensor #4WITAR-B - Image 1 of 1

    Smoke detector, 12/24 Volt, Photo, Relay, Heat, 4-Wire, System Sensor #4WITAR-B

    Brand New · System Sensor
    $109.95
    Free shipping
    26 sold
    ⁣⁣3⁣⁣⁣V⁣⁣⁣ ⁣S⁣X⁣⁣ ⁣S⁣⁣⁣⁣⁣O⁣⁣ ⁣⁣⁣⁣R⁣R⁣⁣ ⁣
  • System Sensor Carbon Monoxide Sensor Fir Hardwired Alarm Systems Brand New - Image 1 of 1

    System Sensor Carbon Monoxide Sensor Fir Hardwired Alarm Systems Brand New

    System Sensor CO 1224 Hardwire
    Brand New · System Sensor
    $59.00
    or Best Offer
    Free shipping
    S⁣U⁣1⁣ ⁣S⁣8⁣р⁣ ⁣9⁣o⁣8⁣n⁣s⁣o⁣r⁣ ⁣e⁣d⁣⁣⁣⁣⁣⁣0⁣6⁣⁣⁣ ⁣
  • 4-in-1 Carbon Monoxide Detector/Gas Leak Detector - Image 1 of 2

    4-in-1 Carbon Monoxide Detector/Gas Leak Detector

    Brand New · System Sensor
    $34.99
    or Best Offer
    $8.19 shipping
    S⁣p⁣o⁣n⁣E⁣ѕ⁣8⁣o⁣r⁣e⁣ ⁣L⁣d⁣⁣C⁣ ⁣⁣0⁣⁣N⁣⁣⁣ ⁣⁣⁣B⁣H⁣ ⁣
  • Safe-T-Alert 62 Carbon Monoxide Alarm 62-542-WT-TR - Image 1 of 1

    Safe-T-Alert 62 Carbon Monoxide Alarm 62-542-WT-TR

    Brand New · System Sensor
    $72.44
    $8.99 shipping
    ⁣⁣F⁣Y⁣ ⁣4⁣7⁣ ⁣⁣R⁣U⁣⁣⁣⁣ ⁣⁣⁣C⁣⁣X⁣ ⁣4⁣L⁣ ⁣⁣⁣M⁣⁣
  • System Sensor 5600 Series Heat Detector Model 5621 - Image 1 of 4

    System Sensor 5600 Series Heat Detector Model 5621

    Open Box · System Sensor
    $24.90
    Free shipping
    ⁣⁣C⁣⁣⁣E⁣ ⁣⁣K⁣⁣I⁣ ⁣5⁣D⁣ ⁣⁣⁣O⁣⁣⁣⁣⁣T⁣⁣ ⁣⁣J⁣⁣
  • System Sensor i3 Series Photoelectric Smoke Detector, Model 4W-B - Image 1 of 4

    System Sensor i3 Series Photoelectric Smoke Detector, Model 4W-B

    Open Box · System Sensor
    (7)
    $39.95
    or Best Offer
    $8.99 shipping
    ⁣M⁣⁣⁣9⁣⁣ ⁣⁣8⁣⁣C⁣⁣ ⁣7⁣J⁣ ⁣G⁣I⁣⁣ ⁣⁣N⁣⁣⁣Y⁣⁣⁣ ⁣
  • CO detector, 12/24 Volt, Trouble Relay, 4-Wire, System Sensor #CO1224T - Image 1 of 1

    CO detector, 12/24 Volt, Trouble Relay, 4-Wire, System Sensor #CO1224T

    Brand New · System Sensor
    $109.50
    Free shipping
    A⁣3⁣ ⁣⁣Q⁣U⁣ ⁣J⁣⁣V⁣⁣ ⁣⁣D⁣7⁣ ⁣8⁣⁣K⁣ ⁣⁣9⁣⁣⁣⁣⁣⁣ ⁣
  • Set 8 Preowned System Sensor 4WTA-B Photoelectric i3 Series Smoke Detector - Image 1 of 4

    Set 8 Preowned System Sensor 4WTA-B Photoelectric i3 Series Smoke Detector

    Pre-Owned · System Sensor
    $100.00
    or Best Offer
    $16.55 shipping
    H⁣P⁣⁣ ⁣⁣⁣⁣1⁣⁣⁣⁣9⁣⁣⁣ ⁣⁣Z⁣⁣⁣A⁣⁣ ⁣⁣H⁣⁣⁣7⁣⁣
  • System Sensor CO1224T Carbon Monoxide Detector White New - Image 1 of 4

    System Sensor CO1224T Carbon Monoxide Detector White New

    Open Box · System Sensor
    (7)
    $63.71
    Was: $74.95was - US $74.95
    Free shipping
    W⁣⁣F⁣ ⁣0⁣⁣M⁣⁣⁣ ⁣⁣⁣⁣⁣0⁣D⁣ ⁣⁣⁣⁣D⁣⁣Y⁣ ⁣⁣⁣7⁣X⁣
  • Ring Smoke/CO Alarm Listener (new) - alerts from existing smoke & CO monitors - Image 1 of 4

    Ring Smoke/CO Alarm Listener (new) - alerts from existing smoke & CO monitors

    Open Box · System Sensor
    (16)
    $15.99
    $8.19 shipping
    0 bids
    3d 21h
    O⁣I⁣ ⁣⁣⁣B⁣⁣K⁣⁣⁣ ⁣⁣⁣⁣⁣⁣7⁣G⁣ ⁣8⁣⁣⁣⁣Q⁣⁣⁣⁣⁣
  • System Sensor 2WTA-B Photoelectric i3 Series Smoke Detector, 2-Wire - NEW - Image 1 of 2

    System Sensor 2WTA-B Photoelectric i3 Series Smoke Detector, 2-Wire - NEW

    Brand New · System Sensor
    (6)
    $64.99
    Free shipping
    43 sold
    ⁣⁣⁣M⁣⁣⁣0⁣ ⁣⁣E⁣⁣⁣⁣B⁣⁣ ⁣⁣⁣T⁣L⁣⁣ ⁣W⁣⁣⁣⁣⁣C⁣
  • 3-Smoke & Carbon Monoxide Detector Alarms battery operated with lcd display - Image 1 of 4

    3-Smoke & Carbon Monoxide Detector Alarms battery operated with lcd display

    Open Box · System Sensor
    $29.99
    Free shipping
    ⁣⁣3⁣F⁣⁣⁣ ⁣R⁣⁣D⁣⁣ ⁣W⁣⁣0⁣ ⁣⁣⁣⁣C⁣P⁣ ⁣⁣0⁣3⁣⁣⁣⁣
  • carbon monoxide detector 91850 msa vintage - Image 1 of 4

    carbon monoxide detector 91850 msa vintage

    Pre-Owned · System Sensor
    $13.50
    or Best Offer
    $8.24 shipping
    ⁣R⁣Q⁣ ⁣J⁣P⁣⁣ ⁣N⁣0⁣⁣⁣ ⁣⁣J⁣⁣⁣L⁣⁣⁣ ⁣K⁣⁣9⁣ ⁣⁣⁣⁣
  • CO detector, 12/24 Volt, Trouble Relay, 4-Wire, System Sensor #CO1224TR - Image 1 of 1

    CO detector, 12/24 Volt, Trouble Relay, 4-Wire, System Sensor #CO1224TR

    Brand New · System Sensor
    $102.95
    Free shipping
    Only 1 left!
    ⁣F⁣⁣⁣7⁣ ⁣⁣A⁣⁣3⁣⁣ ⁣G⁣5⁣⁣ ⁣D⁣M⁣ ⁣G⁣⁣⁣V⁣ ⁣W⁣⁣ ⁣⁣
  • Smoke detector, 12/24 Volt, Photo, 4-Wire, System Sensor #4W-B - Image 1 of 1

    Smoke detector, 12/24 Volt, Photo, 4-Wire, System Sensor #4W-B

    Brand New · System Sensor
    $71.50
    Free shipping
    ⁣V⁣⁣⁣⁣⁣⁣⁣X⁣⁣⁣ ⁣Q⁣W⁣⁣ ⁣Z⁣⁣3⁣⁣ ⁣Y⁣H⁣ ⁣⁣⁣⁣0⁣
  • System Sensor CO1224TR Carbon Monoxide Detector - White - Image 1 of 2

    System Sensor CO1224TR Carbon Monoxide Detector - White

    Pre-Owned · System Sensor
    $28.00
    or Best Offer
    $7.96 shipping
    V⁣6⁣⁣ ⁣⁣⁣⁣Y⁣⁣⁣G⁣⁣⁣⁣ ⁣⁣0⁣3⁣⁣ ⁣⁣3⁣4⁣ ⁣8⁣U⁣⁣ ⁣
  • COSMOD2W - Image 1 of 3

    COSMOD2W

    Open Box · System Sensor
    $40.00
    $15.00 shipping
    2 watching
    ⁣9⁣⁣⁣S⁣⁣ ⁣⁣⁣⁣⁣⁣8⁣Y⁣⁣⁣ ⁣X⁣K⁣ ⁣⁣0⁣⁣⁣⁣5⁣⁣⁣
  • Combination CO & Smoke Alarm Fire - Detectors Home Improvement Safety - Alarm 9V - Image 1 of 4

    Combination CO & Smoke Alarm Fire - Detectors Home Improvement Safety - Alarm 9V

    Brand New · System Sensor
    $18.00
    or Best Offer
    $6.36 shipping
    A⁣X⁣⁣ ⁣⁣O⁣9⁣ ⁣8⁣⁣⁣Y⁣⁣⁣ ⁣⁣⁣N⁣2⁣ ⁣⁣⁣⁣V⁣⁣⁣G⁣ ⁣
  • Vintage Sunbeam Centurion Fire And Smoke Detector 45-21 1976 - Image 1 of 4

    Vintage Sunbeam Centurion Fire And Smoke Detector 45-21 1976

    Brand New · System Sensor
    $49.87
    or Best Offer
    $8.71 shipping
    Only 1 left!
    H⁣⁣⁣U⁣ ⁣5⁣⁣⁣H⁣ ⁣Z⁣⁣⁣⁣⁣R⁣⁣ ⁣⁣⁣⁣2⁣⁣7⁣⁣ ⁣⁣⁣
  • System Sensor CO1224TR Carbon Monoxide Detector - White - Image 1 of 2

    System Sensor CO1224TR Carbon Monoxide Detector - White

    Brand New · System Sensor
    $50.00
    or Best Offer
    $11.95 shipping
    Only 1 left!
    ⁣⁣⁣X⁣F⁣⁣ ⁣F⁣⁣⁣S⁣ ⁣Y⁣⁣1⁣ ⁣⁣⁣D⁣1⁣ ⁣K⁣S⁣⁣⁣⁣ ⁣C⁣
  • Ring Smoke and Co Listener for Ring Alarm White - Image 1 of 1

    Ring Smoke and Co Listener for Ring Alarm White

    Open Box · System Sensor
    $50.00
    or Best Offer
    $8.75 shipping
    ⁣⁣⁣K⁣D⁣ ⁣⁣8⁣⁣⁣I⁣⁣⁣⁣ ⁣⁣8⁣⁣1⁣⁣ ⁣⁣⁣E⁣⁣⁣⁣M⁣
  • EaseAir Indoor Air Quality Monitor – CO2, PM2.5, TVOC, Temp/Humidity *READ... - Image 1 of 4

    EaseAir Indoor Air Quality Monitor – CO2, PM2.5, TVOC, Temp/Humidity *READ...

    Pre-Owned · System Sensor
    $98.00
    Was: $140.00was - US $140.00
    Free shipping
    6⁣S⁣р⁣o⁣n⁣s⁣P⁣o⁣r⁣e⁣d⁣⁣⁣⁣⁣⁣ ⁣G⁣⁣⁣G⁣⁣ ⁣⁣9⁣⁣⁣O⁣
  • EaseAir Indoor Air Quality Monitor – CO2, PM2.5, TVOC, Temp/Humidity, WiFi App - Image 1 of 4

    EaseAir Indoor Air Quality Monitor – CO2, PM2.5, TVOC, Temp/Humidity, WiFi App

    Open Box · System Sensor
    $49.99
    or Best Offer
    $10.39 shipping
    S⁣p⁣o⁣n⁣6⁣3⁣ ⁣8⁣Y⁣s⁣ ⁣8⁣о⁣r⁣B⁣e⁣d⁣⁣ ⁣⁣B⁣B⁣ ⁣R⁣W⁣ ⁣⁣⁣

Results Pagination - Page 1

  1. 1
  2. 2
  3. 3
  4. 4