Smoke & Gas Detectors
smoke & gas detectors β pre-owned
Browse 1,333 smoke & gas detectors β pre-owned on eBay β listings updated every few minutes. All items are pre-owned and sold by eBay sellers directly.

Google Nest T5000SF Temperature Sensor for Nest Learning Thermoset Nest E UVG
Works with the Nest Learning Thermostat (3rd gen) and the Nest Thermostat E. Nest Sensor. Requires one CR2 3V lithium battery. Back Cover.

Yolink Wireless Smoke Alarm Base with main unit, hub purchase separatly required
The Yolink Wireless Smoke Alarm Base with main unit is a reliable and efficient smoke alarm system designed for home security. This unit is specifically constructed as a smoke alarm base with a main unit, providing a comprehensive solution for detecting smoke in the home. The wireless feature allows for easy installation and monitoring, ensuring that you and your family are protected in case of a fire emergency. It's great for ADU monitoring from the main home. Hub will say if your ADU has a smoke. Purchase HUB separately, I don't sell HUB.

HONEYWELL ADEMCO SECURITY 5808W3 WIRELESS PHOTOELECTRIC SMOKE/HEAT DETECTOR USED
1 x 5808W3 Smoke/Heat Detector - used. Built-in wireless transmitter, temporal code 3 sounder. The technician is able to quickly and easily clean the detector chamber without disassembling the detector head.

Google Nest Protect Battery Smoke Detector Carbon Monoxide Alarm Ex 9/30+ Tested
No base, comes as pictured, alarm only The Google Nest Protect Battery Smoke Detector and Carbon Monoxide Alarm is a high-tech home security device that provides peace of mind against potential hazards. With its wireless connectivity and smart home compatibility, this white smoke alarm from Google Nest can be easily integrated into your existing home system. The battery backup ensures continuous protection even during power outages, while the voice alerts and phone notifications allow you to stay informed about any potential issues. Manufactured in 2020, this Nest Protect model (06A) is a reliable and efficient addition to any home security setup.

Airthings Wave Plus 2930 Smart Radon & Air Quality Monitor New (Bulk Available)

First Alert Z-WAVE Smoke & Carbon Monoxide Alarm (ZCOMBO) - with New Batteries
First Alert Z-WAVE Smoke & Carbon Monoxide Alarm with new batteries and hardware as pictured.

Used Airthings 2350 Battery Operated Digital Radon Detector LED Display Portable
For sale is a used airthings digital radon detector. Model 2350.
You save $1.92

Airthings Digital Radon Detector Corentium Home
Airthings Digital Radon Detector Corentium Home In good working condition. Please check all images for the REAL item. No battery included Fast shipping

Exp 2028 Google Nest Protect Smoke Carbon Monoxide Alarm 2nd Gen Battery
Nest Protect Used Refer to photos Everything you see in photos is included ! No screws ! Expiration of 2028

Google Nest Protect Smoke Alarm Carbon Monoxide Detector - Various Expirations
Each detector Includes the factory mounting plate, but no drywall screws/anchors. All in working condition (not sure about the expired ones, I'm not sure how Google's app works with expired detectors).

Nest Protect 3-Pack 2nd Gen Battery 1 Sealed 2 Tested Working Open Box
No remote, no cables, no power adapter. The third unit remains factory sealed in its original tray. The single included backplate is shown in photos. Opening the unopened third nest may yeild an backplate but is not gaurenteed.

Lot Of 2 Google Nest Protect Smoke & Carbon Monoxide Alarms Model 06C

Google Nest Protect Smoke and Carbon Monoxide Alarm 06A BATTERY Exp. Oct 2032
The item will still have minor marks from handling/storage and taking photos. Any fraud attempts will be fought and reported to local and federal authorities. BATTERIES, SCREWS, AND MOUNT INCLUDED .

Vintage GE Home Sentry Model 8201-401C Smoke Alarm (1980s)
This alarm should only be treated as a collectors item, not as a fire safety device due to age. Feel free to ask any questions at any time!

Honeywell Fire-Lite Swift W-SD355 wireless Smoke Detector
Get them before they are gone.

First Alert SC5 Battery Smart Smoke & Carbon Monoxide Alarm
No battery included. Please review provided photos. The photos show everything included with your purchase and the condition of the item. If something is not pictured then it is not included. If you have any further questions please ask. Thank you.
You save $4.00

First Alert 9120B SMOKE DETECTOR Alarm Hardwired with Battery Backup Ionizing
Model 9120B. Hardwired with Battery Backup. Hardwired and uses 9 volt battery backup (battery not included). SMOKE DETECTOR Alarm. First Alert.

FIREX - Smoke / CO Alarms (Model: FADCM & FADC). . .QTY: 5. . .USED/PARTS/REPAIR
Mounting plates.. QTY: 5.. NOTE that the plates for the FADCM alarms differ from the FADC alarms. Instruction guides for both the FADCM and FADC alarms. Smoke / CO (FADCM) alarms.. Manufactured year: 2006.. QTY: 3.

Google Nest Protect Carbon Monoxide Smoke Detector Wired - S3003LWES Exp 2030
Pre-Owned, in good working order; tested and reset to factory default. Includes pictured detector, backplate, and installation hardware as shown in photos, with original box/packaging. Please note: installed batteries are dead and will need to be replaced. They have been kept in unit as the battery door will not close without them installed. Two for sale, one with manual/guides included and one without.
You save $36.00

Airthings Corentium Home Radon Detector 223 Portable Lightweight, Easy-to-Use
RADON REPORT: Generate a radon self-inspection report easily, whenever you need it. FIRST OF ITS KIND: The first battery-operated, digital radon detector.
You save $2.04

Airthings Corentium Digital Home Radon Detector
Works in excellent condition.

First Alert Battery Smoke and Carbon Monoxide Alarm, 2-Pack
Pre-Owned Open Box.

BRK First Alert SMI100-AC Smoke Alarm (2024 JuL 19 ) Used Ships FREE
This smoke alarm, manufactured in 2024, includes a battery backup feature for continuous protection. This has been inspected.

SimpliSafe Smoke and Carbon Monoxide Detector Used
Wireless SimpliSafe combination smoke and carbon monoxide alarm with photoelectric smoke sensing. Ceiling- or wall-mount design with test button. This item is used and in good working order with good cosmetic condition. It has been tested and operates as intended. Compatible with SimpliSafe Gen 3 wireless home security systems (requires an active SimpliSafe monitoring plan and base station unless noted). Original retail packaging is not included unless shown in the listing photos.

Google Nest Protect Wired Carbon Monoxide Smoke Detector Exp July 2033
I have two google nest protect wired carbon monoxide and smoke detectors. They can be purchased together or separate. $300 each. Included is the device, connecting wire, and face plate. These have an incredible later expiration date ... hard to find (Jul 2033). These units are no longer available to purchase at retail and the replacement version that google is supporting does not get the same positive reviews as the nest protect.

*No Base* KIDDE FireX Smoke Alarm i4618AC Hardwired 120V with 9V Battery Backup
*No Base* KIDDE FireX Smoke Alarm i4618AC Hardwired 120V with 9V Battery Backup. Condition is For parts or not working. Shipped with USPS Ground Advantage.

First Alert BRK 9120B Smoke Detector Alarm AC Powered With Battery Backup
First Alert BRK 9120B Smoke Detector Alarm AC Powered With Battery Backup. Condition is Used. Shipped with USPS Ground Advantage.
You save $3.51

ONE KIDDE FIREX 120V WIRING HARNESS PIGTAIL USED (SET OF 4)
Please view photos carefully prior to purchase. This set includes 4 used Kidde pigtail terminal wires. Fits most kidde firex detectors, but please verify proper fit for yours. If you have any questions please feel free to reach out! Ships within 24 hours!

Honeywell Silent Knight SD500-ANM P/N 122827 ADDRESSABLE NOTIFICATION MODULE
Item was taken out of a job site that had a bad panel. The actual condition of this device is not known. If it is defective, we will replace it.

Honeywell Fire-Lite Swift W-SD355 wireless Smoke Detector
Get them before they are gone.

Google Nest Protect Smoke & Carbon Monoxide Detectors White Wi-Fi Battery
Selling because I am getting away from nest. Still works perfectly

Lot of 5 Airthings View Plus Smart Air Quality Monitor AS-IS Parts Only
Sensors: Radon, PM2.5, CO2, VOC, Humidity, Temp, Pressure. UNIT DETAILS & TESTING: . - Model: View Plus. - Power: All units power on successfully via both USB-C and batteries.

Airthings 2920 Wave Mini indoor Air quality monitor (Price is for 2 pieces)
The Airthings 2920 Wave Mini indoor Air quality monitor is a set of two sleek white devices that monitor and improve indoor air quality. Weighing only 0.3 lb, they are lightweight and easy to install in any room.

Kidde 900-CUAR Smoke & Carbon Monoxide Detector LOT OF 8 *USED / OPEN BOX*
Refer to photos. Message me with any questions or concerns. Ship same day order.

First Alert BRK PC1210V Smoke & Carbon Monoxide Detector Alarm w/10 Year Battery

Nest Protect Smoke Detector Carbon Monoxide 2nd Gen -READ DESC
Comes as pictured. History unknown so listing as used. Unit has a small crack on the front button (pictured) some dust on it and minor marks on the back from being put together. My guess is it was purchased then someone changed their mind, but as the title says I donβt know the history of the device. Accessories are in great shape, even the screws look unused. All that aside, the unit works and is ready to go! Expires in 2030
You save $7.50

Kidde Firex i4618AC Ionization Smoke Alarm / Detector Used 2017 No Base 9V

FirstAlert Z-Wave Plus Smoke/CO2 Detector, 2nd Generation (ZCOMBO-G) Lot Of 5
FirstAlert Z-Wave Plus Smoke/CO2 Detector, 2nd Generation (ZCOMBO-G) Lot Of 5 Will receive everything pictured, all 5 detectors and one ring All were tested and work See pictures

2GIG Wireless FireFighter Smoke Detector Sensor-Transmitter (2GIG-FF-345)
The 2GIG Wireless FireFighter Smoke Detector Sensor-Transmitter (2GIG-FF-345) is a white, battery-powered smoke detector that is compatible with 2GIG systems. It includes a battery backup feature and is compatible with Google Assistant and Amazon Alexa for smart home integration. This unit is designed for home security and improvement, providing a reliable early warning system for potential fires. Made in China, this smoke detector is a crucial component in ensuring safety and peace of mind in any home.

Apollo 51000-600 Wireless Combo CO2, Smoke, Heat Detector - Fresh Batteries
Pulled from working installation - Fresh batteries installed - Good through September 2032.