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Household Sensors & Alarms Categories
Best Choice Mengshen 
Mengshen Motion Sensor Alarm, Wireless Doorbell Alert for Front Door Door Entry Driveway Mailbox Home Shop Visitors with Wireless Motion Sensor: The transmission range of the motion sensor alarm is up to 280m/918ft (the distance from the detDaytech 
Daytech Door Sensor Chime Entry Alert Chime Wireless Door Window Open Alarm with 5 Volume Levels for Home Store Apartmen How This Door Open Sensor Alarm Works: Door sensors are devices that let you know when someone has opened a door. Door sBest Value Mengshen 
Mengshen WiFi Water Leak & Water Level Detector, 2-In-1 Tuya Smart Sensor Alarm Loud Volume APP Alert Monitoring with 6. 💧【Dual Sensor Water Alarm】2 in 1, including water leak probe and water level probe. It can not only detect water leaks,meross 
meross Smart Presence Sensor, Matter Motion Detector with Light Sensor for Home Automation and Security, Pet Friendly, C Matter Multi-platform Compatibility: Use any Matter-supported hub (e.g., Amazon Echo, Google Nest) to control this preseWinhon 
Motion Sensor Alarm,Wireless Motion Detector Door Chime Doorbell for Home Store Business,Caregiver Reminder for Elderly, 【Application】Home Use: Get real-time alerts when someone approaches your house, monitor patient care activities, or keepeMagTech 
eMagTech Water Leak Sensor Water Leak Sensor Detector 120dB Water Leak Alarm Detector Water Overflow Alarm Detector for Powerful Alarm: Boasting an ear-piercing 120dB alarm sound, the device ensures attention and action. The alarm persistsUanTii 
UanTii Smart Water Leak Alarm Sensor Tuya WiFi Water Leak Detector Flood Detector with 100dB Loudly Alarm Sound Works wi [APP Remote Control] Works with Smart Life/Tuya Smart App; Receive alarm push remotely at any time through the mobile phDogxiong 4 Pack Security Window/Door Alarm, Door Open Chime, Magnetic Burglar Alert Sensor, Loud Door Alarms for Kids Safety, DIY Big LOUD ALARM – door window sensors loud enough to detects entry, prevent kids and babies going out the house, protectiDaytech DAYTECH Door Alarm Sensor Volume Adjustable Door Open Sensor Chime 0-120 dB Window Alarm with 4 Modes for Kids Safety De Volume Adjustable Door Alarm: This door and window alarm is used to alert you when a door or window is opened by 0-120DBDaytech DAYTECH Door Alarm with Remote, 0-120dB Door Alarm Sensor When Opened Window Security Alert with 4 Working Modes for Kid [Window&Door Open Alarm] This door alarm alerts you when a door or window is opened by emitting a 120 decibel sound, whiMeichoon Meichoon Motion Sensor Alarm Wireless Detector Home Security Alert System Doorbell for Front Door Indoor Room Entry Driv ✨Expandable Wireless Home Security - Independent alarm horn,maximum 113dB, can effectively scare the thieves and intrudeMengshen Mengshen Door and Window Alarm, Anti-Theft Burglar Wireless Alarm with Remote Control for Home Security, Easy to Install Home Security Alarm: Super loud alarm of 105dB, scare thief away,BUBUCAM WiFi Water Leak Detector, Smart WiFi Water Detector, APP Remote Control Water Sensor for Kitchens, Basements, Sinks, and *Smart Life APP: Monitor and detect water leaks remotely via the Smart Life mobile app, provide timely notifications andGoerpn 2 Pack Ultra Slim Window Alarm - 130dB Vibration Sensor for Security - Glass Break Alert for Home, Office, Dorm Room, RV 【Ultra Thin Window Alarm】A slim, modern shock sensor alarm designed for windows and doors.AiBest Door Window Alarm, Burglar Alarm, Home Security Wireless Magnetic Sensor Anti-Theft Alarm (Home Alarm (12 pcs)) Super loud 95 dB alarm. When someone opens the door or window illegally (the relative position of the primary and secondGeneric Propane Detectors for Home - High Sensitivity Leak Alarm | 12V High Sensitivity RV Propane Alarm | Leak Detection for Ho ✈Constant Protection: Suitable for any place where a 12V power supply is present, this propane detector ensures ongoingEPTTECH EPTTECH Smart TLC 2326-WF-S Tuya APP Efficient Solar Panel Rechargeable Battery Liquid Level Monitor WiFi Water Oil Tank LONG MEASURING DISTANCE: 10cm to 2.9m(4 to 114 inches) from the sensor, which is suitable for different tanks.SECRUI SECRUI Door Chime, Wireless Door Alarm Sensor with 500ft Range 32 Chimes Adjustable Volume Mute Mode LED Indicators – Do Easy to Install: The SECRUI door sensor installation operation is simple and does not require the use of any wiring or sCHUSHEN Solar Motion Sensor Alarm Outdoor Solar Alarm 120dB Loud Siren LED Strobe Lights Sound Security Alarm Adjustable Sensing 🥁 Solar Energy Alarm Light: this solar alarm strobe light can frighten away intruders and thieves by siren and strobe lVITITE Carbon Monoxide & Combination Gas Detector, 4 in 1 Plug in CO, Natural Gas, Propane, Temp and Humidity Gas Alarm; Design 4-in-1 Combination Gas Detector: The YC302 Pro+ uses high-precision sensors to monitor CO, natural gas, propane, temperaMETAK 5 Pack Water Leak Detectors for Home, 100dB Water Sensor Alarm for Basement, WD60 Flood Leakage Detection Devices for Pi Leaking & Dripping: 2 water sensitive probes on the front for monitoring pipe/drain drip and 4 rear probes for detectionHoneTeek Motion Sensor Detector Door Chime for Business Store Entry Alert, Welcome Buzzer Monitor Doorbell Alarm for Home Elderly ✨【Welcome Buzzer Monitor】The owners can use the doorbell to be alerted when people enter or leave. Use it to detect visiWuloo Wireless Driveway Alarm 1800 Feet Long Range Motion Sensor Alert System Driveway Detector for Home with 1800mAh Recharge Reliable & Dependable: Guaranteed 1/3-mile long range (1760 ft; 536m) tested in real-world settings with trees, buildingSYNLETT SYNLETT Bed Alarm Caregiver Pager with Wireless Motion Sensor Alarm Indoor Fall Prevention for Elderly Monitoring Senior PORTABLE BED ALARM DEVICE: The portable bed alarms and fall prevention for elderly device is applicable at various areasMengshen Mengshen Motion Sensor Alarm, Driveway Entry Alert Support 5 Modes, 36 Tunes, Long Transmission Distance (Remote Control 5-In-1 Multifunctional: Receiver has 5 modes, Welcome/ Doorbell mode(36 Tunes available)/ Alarm/ Colorful light/ Night LX-Sense X-Sense Wi-Fi Water Leak Detector Kit, Smart Water Sensor Alarm with App Alerts and Ultra-Slim Design, Water Alarm Leak Never Miss a Leak: When a water leak is detected, a red light will flash on the water leak detector and the base stationMETAK WiFi Water Leak Detector for Home with App Notification, 1 Gateway + 6 WD61 Sensor, 120dB Water Flood/Drip Alarm for Bas [APP Notification] When the water leak detector senses a leak, the 2.4GHz WiFi gateway instantly sends real-time alertsSPARTHE SPARTHE Gas Leak Detector Alarm for Caravan, Boats Gas Detector-Accurate detection and security protection.Fast response, high-pitched alarmSECRUI SECRUI Wireless Door Chimes When Entry for Business/Home/Office/Store (500ft Range 32 Chimes Adjustable Volume) Door Ope Easy to Install: The SECRUI door sensor installation operation is simple and does not require the use of any wiring or sWuloo Solar Driveway Alarm Wireless Outside 1800ft Range, Outdoor Motion Sensor & Detector Driveway Alert System with Recharge Reliable & Dependable: 1/3-mile long range (1760 ft.; 536m) tested in real-world settings with trees, buildings, walls,Pomya Wireless Security Keypad Alarm System, PIR Motion Sensor Alarm Password Keypad Remote Infrared Detectors with Panic Butt This Motion Sensor Alarm is for protecting your property against unwelcome intruders.CPVAN CPVAN 125dB Loud Motion Sensor Alarm with 328ft Remote Control (40ft PIR Detector, Batteries), Indoor Wireless Infrared Super Loud and Easy to Use👉 CPVAN Motion Sensor Alarm is designed with 125dB alert device and simple operation, which cBESTOYARD BESTOYARD Smart Water Leak Detector High Sensitivity Water Level Sensor Reliable Alarm for Homes Offices Warehouses Easy Consistent reliability: built for dependable performance and longterm use,water for home,high water alarmSABRE SABRE Wired Water Leak Flood Alarm Sensor with 110 dB Siren - DIY Easy Installation 23% Off MOCREO MOCREO SW2 Water Leak Detector Sensor with 95dB Alarm, Hub Required, No Subscription Fee, Home Wireless Flood Monitor fo PROTECT HOME FROM COSTLY WATER DAMAGE - Note: SW2 water leak detector can not work alone, it must work with MOCREO Hub(SDaytech DAYTECH Motion Sensor Door Chime, Wireless Doorbell for Business Entry with 3 Working Modes Welcome Infrared Motion Sens 【Motion Sensor Doorbells for Entry】Place the motion sensor at front door, the Receiver will sound to remind you that somCPVAN CPVAN 125dB Loud Motion Sensor Alarm with 328ft Remote Control (40ft PIR Detector, Batteries), Indoor Wireless Infrared Super Loud and Easy to Use👉 CPVAN Motion Sensor Alarm is designed with 125dB alert device and simple operation, which cBetterlink 1/2 Mile Long Range Solar Wireless Driveway Alarm System IP65 Weatherproof Outdoor Motion Detectors&Sensor 120dB Siren S Easy to install and expand: This wireless solar driveway alarm system is easy to install. It can be installed on walls,METAK METAK Water Leak Detector Sensor Alarm: Home Water Flooding Monitor Smart Sink Overflow Monitoring Adjustable Wet Moistu Drip & Leak Alerts: Water leak detector alarm is designed with 4 rear water leakage detection probes and 2 front drip prX-Sense X-Sense Wi-Fi Water Leak Detector, Smart Water Sensor Alarm, Water Detector Alarm with 1700 ft Transmission Range for Ki Ready to Use: Download the app, connect the devices to the app via the 2.4 GHz Wi-Fi network (incompatible with 5 GHz) aUanTii UanTii Tuya WiFi PIR Motion Sensor Movement Detector Alarm Smart Life APP Wireless Home Security System Compatible with 【APP Remote Control Tuya WiFi Motion Sensor】Simple download APP "Smart Life/Tuya Smart" in App Store or Google Play addgernie Gas Detector, Portable 4 Gas Monitor with Sound Light Vibration Alarm for H2S O2 CO LEL, 4 in 1 Rechargeable Accurate Me [Backlit Display] The gas monitor has a high resolution backlit screen that provides clear readings day and night, ensurAzdBvae High / Low Water Level Sensor Detector Alarm 120 dB Red Strobe Siren, Adjustable Alarm Volume, Sump Bobber Water leak Se 【High and Low Dual Probe Sensoe Design】- It can detect water shortage(low level) or overflow(hige level). You can chooseHTZSAFE HTZSAFE Rechargeable Dual-Direction Motion Sensor & Detector, 35 Optional Chimes&Voices, Differentiate Come & Go with Di Wide Range Of Applications:The indoor motion sensor built-in high quality speaker and 35 optional chimes&voices which caShelly Shelly Flood | Wireless Flood Sensor with Temperature Measurement | Home Automation | iOS Android App | Dripping & Leaki Shelly Flood is a smart water leak detector connected by wifi. It can also measure the floor temperature in your home. TDaytech DAYTECH Freezer Door Alarm with Delay 1/2/3/4 mins When Left Open Window Chime Close Reminder Refrigerator Door Alarm 0 Freezer Door Alarm When Left Open: When the alarm and magnetic sensor are separated by more than 0.6inch(1.5cm), The alaEacam Eacam WiFi Siren Alarm Sensor Smart Alarm Siren Home Security System Tuya Smart Life APP Compatible with Alexa Google Ho 🌹 【Siren with Temperature and Humidity Sensor 3IN1】APP sets the temperature and humidity alarm range in advance, detectSwitchBot SwitchBot Door Alarm Contact Sensor - Smart Home Security Wireless Window Alarm and Door Sensor, Add SwitchBot Hub Mini [Window & Door Alarm Sensor for Home Security] SwitchBot Contact Sensor can detect the opening/closing of doors and windEPTTECH EPTTECH TLC2206 Tuya Smart Life Mobile APP Wireless WiFi Remote Ultrasonic Real-time Reminder Contactless Outdoor Waterp LONG MEASURING DISTANCE: 10cm to 3.0m(4 to 118 inches) from the sensor, which is suitable for different tanks.Lockmaner Lockmaner Wireless Strobe Alarm Light Set Sound Outdoor Alarm Siren for 433MHz Wifi GSM Alarm System for Home,Farm [Adjustable Sensitivity to Avoid False Alarms]Stylish and design, suitable for outdoor use.High-intensity warning lightsjojofuny jojofuny 2pcs Water Leak Detector Alarm for Sinks and Washing Machines High Sensitivity Overflow Monitoring Device Sound Water sensor alarm:high sensitivity, can detect water level changes in a timely manner, avoiding damage to household appGeneric [2 Pack] Zigbee Door/Window Contact Sensor with Lux Light Detectors – Compact - Real-Time Alerts, Smart Home Automation, 🚪 Instant Open/Close Alerts Get notified on your phone the moment a door or window opens—perfect for home security, chiMengshen Mengshen Motion Sensor Alarm Kit - Home Security Alarm System Support 5 Modes, 36 Tunes, Long Transmission Distance (Rem Home Security Alarm Kit: Includes 1 Receiver + 1 Contact Sensor + Infrared sensor + 1 Remote Control. According to yourB-Qtech B-Qtech Carbon Monoxide Detector Alarm with Digital Display and Replaceable Battery Operation, CO Detector Alarm with Te The carbon monoxide (CO) detector is equipped with a high-precision electrochemical CO sensor, which can quickly detectLETWESAF Wireless Radar Motion Alarm System - 1/2 Mile Range, Hideable Motion Detector, IP65 Waterproof, Rechargeable Battery - I 𝐀𝐝𝐯𝐚𝐧𝐜𝐞𝐝 𝐑𝐚𝐝𝐚𝐫 𝐓𝐞𝐜𝐡𝐧𝐨𝐥𝐨𝐠𝐲: This smart motion sensor alarm system uses millimeter-wave radar for sUanTii UanTii Tuya WiFi Door Window Detector with Light Sound Alarm Wireless Door Alarm Sensor for Home Security Smart Home Doo 【No hub required】The window Door alarm sensor works with directly Tuya Smart/Smart Life App and Alexa Google Home, no huEmerald Planet RF Interconnect Photoelectric Smoke Alarm with 10 Year Lithium Battery | Emerald Planet Ranger (EP-RANG-RF-10) 10-year 3V lithium batteryHEALTHY CHOICE Healthy Choice 70-Liter Auto Sensor Trash Bin - Wave Your Hand for Auto Open/Close, Waterproof Lid, Optional Manual Oper Auto Sensor Operation: Enjoy hands-free waste disposal by simply waving your hand over the sensor to automatically openGuDoQi GuDoQi Water Leak Detector With Loud 130dB Alarm - Flood Sensor for Home Security, Bath Overflow Detection - Battery Inc Powerful 130dB alarm, easy to be heardintendvision Gas Leak Detector, Natural Gas Detector with 3-Sensitivity Adjustable, Temperature & Humidity Measurement, Audible & Vis 【3 in1 Portable Gas Leak Detector】This 3 in 1 gas leak detector is designed to combine the functions of gas leak detectoEPTTECH EPTTECH Smart TLC2326P Remote Detector Display Screen Tuya Smart Life Mobile APP Liquid Water Oil Fuel Level Tank Monito Tihebeyan Sensor Alarm Light Alarm Light Duration for Toilet Hospitals (#2) [Warning effect] High section and bright light for effective alerts.Daytech DAYTECH Door Alarm Sensor Window Alerts for Home Security 120dB Door Open Alarm with Low Battery Alert for Kids Safety D Door Alarms When Opened: DAYTECH Door alarm sensor can detect the opening/closing of doors and windows, guarding securitGAIN EXPRESS Hydrogen Sulfide Detector H2S Gas Detector Monitor Meter Portable Sound and Flash Alarm h2s Gas Monitor 0~100ppm Electro 💨MEASUREMENT RANGE: 0~100ppm0; 0.01VOL%; 1~152 mg/M³; 0~0.23LEL% with 500ppm maximum overload.12% Off NULYLU NULYLU Water Overflow Detector for Tea Set Tea Bucket Leak Alarm Simple Efficient for kitchen--the tea water bucket full water reminder is designed to be simple and easy to use, making it more user-frie12% Off S SELDORAUK S SELDORAUK Dog Barking Alarm Motion Sensor - 1000 Feet Wireless Home Security Driveway Alarm Kit (1Receive+1Motion Dete 【6 Realistic Dog Barks sounds】 : 6 dog barking choices in big volume .The motion detector very sensitive,Pir human bodyUanTii UanTii Smart Vibration Detector Tuya WiFi Vibration Sensor Smart Home Security System Support Smart Life App Remote Moni 【App Real-Time Monitor】Works with Smart Life/Tuya App, whenever and wherever you are, once the vibration sensor detectsEPTTECH EPTTECH Smart TLC 2326-WF-S Tuya APP Efficient Solar Panel Rechargeable Battery Liquid Level Monitor Wifi Water Oil Tank LONG MEASURING DISTANCE: 10cm to 2.9m(4 to 114 inches) from the sensor, which is suitable for different tanks.MTI MTI Industries 30-442-P-WT Propane Gas Alarm – White style: flush mount; color: whiteActpe Motion Sensor Doorbell for Business Store Entry Alert Welcome Buzzer Monitor Alarm, Outdoor Door Chime Kit for Home - LE ✨【Easy, Fast, Wire Free Installation】 Infrared sensor detects motion and sends a signal to the receiver. Chose from 36 RLancoon Lancoon Solar Sound & Light Alarm Outdoor Motion Sensor Waterproof Device 110db Siren Sound Alert Flash Warning Security 🏡【Animal Repellent Outdoor】The performance of our device is based on a double effect. First, the rapid flashing of theKOQICALL KOQICALL Solar Alarm Moiton Detector 120 dB Adjustable Volume Strobe Light Audible Security Alarm IP65 Waterproof Outdoo 【Two Charging Methods】The mobile detector is powered by rechargeable lithium battery. The mobile detector can be chargedGeneric Propane Leak Detector | 12V High Sensitivity Leak Detector - Leak Detection for Home, Kitchen, Trailer, or RV, Leak Dete High Decibel Audible Alarm: Our propane detector provides peace of mind by detecting leaks and sounding an audible alarmXimimark Ximimark 2Pcs Water Leak Alarm Flood Level Bath Tub Sink Overflow Detector Sensor Home Garage Kitchen Security Alert 120 120dB loud alarm voice, keep alarm to notice you or neighbors until the water dry or sensor turn off, low cost and effecEP ESSENTIAL PRO Wireless Digital Weather Station LCD by EssentialPRO With Indoor and Outdoor Temperature and Humidity Sensor | Digital T ALL IN ONE REAL TIME MONITORING: Provide real time live temperature, humidity data and calendar function, the EssentialPMellisso Mellisso 3 Pack Solar Strobe Light with Motion Sensor Alarm 129DB Sound Security Siren IP65 Waterproof for Villa Farm Ya Long lasting:After fully under sunlight, the sound alarm can work for about 30 days. No worry run out of power.EPTTECH EPTTECH Smart TLC 2326-WF-S Tuya APP Efficient Solar Panel Rechargeable Battery Liquid Level Monitor WiFi Water Oil Tank LONG MEASURING DISTANCE: 10cm to 2.9m(4 to 114 inches) from the sensor, which is suitable for different tanks.LEAFLEX 2 Pcs Garage Door Bracket for Aqara T1 Alarm Entry Sensors, Quick Installation & More Protection for Your Garage Door, G Package includes: 2 Pcs Garage Door Bracket, Includes pastes and screws.Plyisty Wireless Door Alarm, 120dB Lightweight Prevent Theft ABS Door Alarm Sensor Easy Installation Sturdy for Home 120DB ALARM SOUND: Wireless door alarm will sound a high pitched alarm up to 120dB upon detecting a vibration, scaring aHEALTHY CHOICE Healthy Choice 60-Liter Auto Sensor Trash Bin - Wave Your Hand for Auto Open/Close, Waterproof Lid, Optional Manual Oper Auto Sensor Operation: Simply wave your hand over the sensor to automatically open and close the lid, providing a touch-Jectse High Sensitivity Gas Monitor with 4 in 1 Measurement Rechargeable Battery, Sound Light Vibration Alarms, Backlit Display [Multiple Charging Options] This gas tester is rechargeable and can be charged using USB from a computer, car, power banINKBIRDPLUS INKBIRDPLUS PM2.5 Indoor Air Quality Monitor, Portable PM2.5 PM10 and Temperature Humidity Detector, with Sound and Ligh [4 in 1 Detection] This multifunctional indoor air quality monitor is designed to detect 4 key factors in the air, incluLUCKYDUO LUCKYDUO WiFi Sump Pump Alarm, Smart Water Level Alert with App Notification, High Water Lever Sensor Detector for Indoo Smart Water Lever Alarm: Keep your home safe with high water level alarm that features a 90dB siren and LED strobe for iLETWESAF Wireless Radar Motion Alarm System, 1/2 Mile Range, Hideable Motion Sensor & Detector, Rechargeable Battery, IP65 Waterp 𝐀𝐝𝐯𝐚𝐧𝐜𝐞𝐝 𝐑𝐚𝐝𝐚𝐫 𝐓𝐞𝐜𝐡𝐧𝐨𝐥𝐨𝐠𝐲: This smart motion sensor alarm system uses millimeter-wave radar for sRisinglink Risinglink Smart Water Level Monitor, WiFi-Enabled, Text/Email Alerts, Indoor/Outdoor Detector, Battery Powered, Stainle Easy Setup: No need for apps or hubs, simply connect the device to your WiFi network(Note: only 2.4GHz WiFi supported).Sensereo Fuel Gas Detector Plug in Elegant Design Funzionamento tramite alimentazione plug-in per un monitoraggio continuoYaSao YaSao Weather Station, Sunrise and Sunset Weather Station Multi-Function Alarm Clock Thermometer Hygrometer Touch Screen 💌[Multifunctional Weather Station: large touch screen with backlight, clearly display time/date/calendar/temperature/huTHE BASEMENT WATCHDOG The Basement Watchdog Compact 110 dB 360° Water Alarm Detects Water on All Sides (BW-WA360) Patented design allows it to detect water on any sideScondaor Scondaor Gas Leak Detector for H2S CO O2 and LEL, Portable Multi Gas Detector with Audible, Visual and Vibration Alarms, 【High Sensitivity and Quick Gas Response】 The gas analyzer equipped high quality gas sensors with excellent sensitivityGeneric Air Quality Sensor Module - High Precision Air Quality Detection Sensor,Portable Dust Sensor, PM2.5 Concentration Sensor Precise Design: By utilizing our Dust Sensor Module, you can detect PM2.5 concentration in the air with high accuracy, mAeipou 50 Pcs Smoke Detector Covers Fire Alarm Plastic Stretch Dust Caps To Protect Smoke Alarms During Renovation Work & Decor Package Content: You will receive 50pcs red smoke detector alarm covers, ensuring a long-lasting supply for your home saKONLEN Tuya Smart Home Water Level Sensor WiFi Controller Leakage Flood Alarm Swimming Pool Pump Tank Flow Detector It is a type of WIFI intelligent water level controller, which can be set by APP to realize water level monitoring, WateForsensal 4 Gas Monitor Multi Gas Detector EX O2 H2S Monitor Clip on, 3000mAh Rechargeable 4 Gas Meter View Records and Curve, Por 【4 Gas Monitor Multi Gas Detector】The 4 gas Monitor measures gases such as carbon monoxide (CO), oxygen (O2), hydrogen sEPTTECH EPTTECH Smart TLC 2326-WF-S Tuya APP Efficient Solar Power Supply Accurate Liquid Level Monitor WiFi Water Oil Tank Leve LONG MEASURING DISTANCE: 10cm to 2.9m(4 to 114 inches) from the sensor, which is suitable for different tanks.Tapo Tapo H500 HomeBase 16GB Built-in Memory Expandable up to 16TB Supports 16 Tapo Cameras & 64 Sensors Local Storage HDMI 5 Local storage without monthly fees: Built-in 16GB eMMC memory, expandable up to 16TB via an additional 2.5" SATA HDD/SSDEPTTECH EPTTECH Smart TLC2326 Tuya Liquid Level Monitor APP Oil Water Indoor IP65 Alarm Sensor Household Indicator Ultrasonic We LONG MEASURING DISTANCE: 10cm to 2.9m(4 to 114 inches) from the sensor, which is suitable for different tanks.TopHomer 3Pcs Smoke Detection Sensor, MQ-2 Liquefied Gas Butane Methane Sensor Module for Gas Leak Monitoring Device - MQ-2 Smoke Liquefied Gas Butane Hydrogen Sensor10% Off intendvision Natural Gas Detector, Gas Leak Detector with a 11inch Probe to Situate Combustible Gas Leaks for Propane, Natural Gas, M Detects a Wide Range of Combustible Gases 1-50000PMM or 1%-100%LEL alarm range. Detects a large number of flammable gaseLICAEVEY Air Quality Monitor Indoor, Portable CO2 Detector Thermometer Hygrometer, USB Charging Air Quality Tester for Home Schoo TVOC SENSOR: The CO2 detector with TVOC sensor is designed to detector the CO2 value, temperature and humidity of air quCINARIS O3 Meter Ozone Detector 3.5 Inch TFT Multifunction Air Quality Monitor Desktop Ozone Tester Portable Ozone Meter USB CHARGING: The O3 detector is equipped with a USB charging port and a high capacity 2000mAh lithium battery that warn