Product Carousel Tabs
SONOFF Zigbee 3.0 USB Dongle Plus
Note 1: If you want to connect 1.5m USB extension cable for better signal range, click this link to buy.
Note 2: Dongle Plus is out of stock for the moment due to large market demand and it will restock soon. You can pre-order now but it may be delayed to ship until then.
SONOFF Smart Stackable Power Meter
【Connect up to 32 SPM-4Relays】One SPM-Main can be connected 32 SPM-4Relays. Each SPM-4Relay has 4 isolated channels to help you manage devices more conveniently.
【Power metering】You can monitor the power consumption by checking eWeLink App on your mobile phone. Obtaining current, voltage and power easily.
【Max. 20A/Gang】Each channel can support maximum current of 20A, no fear of high power load.
【Communicated by RS-485】The SPM-Main communicates with the SPM-4Relays through RS-485, which allows for multi-terminal and stable long-distance data transmission.
【Overload Protection】Once the overload protection is enabled, it can protect your devices from burning out.
SONOFF Smart Stackable Power Meter in stock at the half of October, you can pre-order now but it may be delayed to ship until then.
SONOFF MS01- Smart Soil Moisture Sensor
【Monitor Soil Moisture】Works with TH10/16 to monitor your plants’ soil moisture.
【DIY A Smart Watering Device】DIY your sprinkler to water automatically according to the setting moisture value.
【IP55 Waterproof 】IP55 waterproof assure you water flowers freely without taking the sensor out.
【Voice Control 】Ask your Google Assistant for humidity conveniently.
Work with AL560 to extend measure distance.
Note : We will have SONOFF MS01- Smart Soil Moisture Sensor in stock at the half of November, you can pre-order now but it may be delayed to ship until then.
Inteligent Automatic WiFi Curtain Switch Module DIY Smart Home for Roller Shutter Motor Google Home Amazon Alexa Voice Contro
Inteligent Automatic WiFi Curtain Switch Module DIY Smart Home for Roller Shutter Motor Google Home Amazon Alexa Voice Contro
SONOFF POWR3 High Power Smart Switch
【25A/5500W Highest Output Power】POWR3 has the highest output power to make your high-powered devices smart, or as a single room-meter to measure power consumption.
【Measuring Power Consumption】Keep track of active power, current and voltage of your appliances on App
【Overload protection】Once an abnormality was detected, the power will be cut off to avoid device damage and danger.
【One-tap switch on/off remotely】POWR3 can cut off power wherever you are that can ensure the safety of your appliances and save on hidden electricity bills
【Voice Control】Compatible with Amazon Alexa, Google Assistant, SmartThings, and Alice. Just speak out your command, the smart device can do on/off as you say.
Smart Wifi Black wall touch Modular switch with Smart Home edge 4 Gang works with Alexa IFTTT,Google
Smart Wifi Black wall touch Modular switch with Smart Home edge 4 Gang works with Alexa IFTTT,Google
Smart WiFi Smart Touch Panel Dimmer Light Switch 2 Gang Modular switch works with Alexa ,Google
Smart WiFi Smart Touch Panel Dimmer Light Switch 2 Gang Modular switch works with Alexa ,Google
SONOFF DW2-RF – 433MHZ RF Wireless Door/Window Sensor
Note: SONOFF DW2-RF doesn’t come with batteries into package, and it requires gateway like SONOFF 433MHz RF Bridge to use.
Click to view the difference among DW2-RF, DW2-WiFi and SNZB-04
Household Oxygen Inhaler | Mini Oxygen Pressure Regulator | G5/8-14 Male Thread Oxygen Pressure Reducing Valve Accurate Flow Oxygen Meter for Oxygen Inhalation
Household Oxygen Inhaler | Mini Oxygen Pressure Regulator | G5/8-14 Male Thread Oxygen Pressure Reducing Valve Accurate Flow Oxygen Meter for Oxygen Inhalation
Powertip PC1602F-B Alphanumeric LCD Display 16×2
SONOFF MINIR2 – Two Way Wi-Fi Wireless Smart DIY Switch Turn traditional switch to Smart WiFi Switch With Timer Internet Work With AMAZON Alexa,google Home ,Nest
SONOFF MINIR2 – Two Way Wi-Fi Wireless Smart DIY Switch Turn traditional switch to Smart WiFi Switch With Timer Internet Work With AMAZON Alexa,google Home ,Nest
Home Portable Intelligent Oxygen Concentrator Generator machine Infrared Remote Control1-7L
Home Portable Intelligent Oxygen Concentrator Generator machine Infrared Remote Control1-7L
Complete plastic outer shell, safe and reliable.
SONOFF Motion Sensor BASE For SONOFF SNZB-03/PIR3 Universal Joint
Motion Sensor BASE, Suitable for SONOFF SNZB-03 and SONOFF PIR3.
With the universal joint, the sensor can be flexible to rotate a full 360°horizontal angle and 90°vertical angle which allows you to adjust the sensor into an optimal angle to view everything in your home (The sensor doesn’t move on its own based on your motion). Another convenience for your home is that you can use the sensor for a position where the movement is not easy to be detected via mounting it in the universal joint, and just rotate the universal joint head to get a wonderful detecting angle.
Hospital Portable Intelligent Oxygen flow/purity Concentrator Generator machine 5L
MCU Intelligent control
Real-time oxygen concentration detection
24 hours no-stop working
Practical patented technology
one-piece housing shell
Multipurpose :Atomization /with Ventilator
Intelligent alarm system : Low oxygen flow/purity ,overload , power failure
Multicolor RBG Smart LED Light Strip SONOFF L1 Lite – 5M Work with Alexa and Google Home hands-free voice control
Multicolor RBG Smart LED Light Strip SONOFF L1 Lite – 5M Work with Alexa and Google Home hands-free voice control
Note:
1. L1 lite is not water-proof, don’t use it outdoors. If need waterproof light strip, move to SONOFF L1.
2. To make it extendable, you can control multiple light strips using grouping feature
Home Portable Intelligent Oxygen Concentrator Generator machine Infrared Remote Control 7L
Home Portable Intelligent Oxygen Concentrator Generator machine Infrared Remote Control 7L
Complete plastic outer shell, safe and reliable.
Wireless WiFi LPG Gas Detector Alarm Leakage Sensor Natural,PROPANE Gas Leak Detector Alarm APP Control
Wireless WiFi LPG Gas Detector Alarm Leakage Sensor Natural,PROPANE Gas Leak Detector Alarm APP Control
1. LCD Screen Clearly Shows: Easy-to-read and clearly digital display shows combustible gas concentration and WiFi signal.
2. Natural Gas & LGP Detect: Detect the natural gas (Methane) and LPG (Liquefied Petroleum Gas) leakage
3. 85dB Alarm Sound & APP notification
4. WiFi connection, smart APP remote control. With manually test, manually mute. To temporarily mute the alarm in the gas alarm state.
5. New Design and Easy-to-install
SONOFF Zigbee 3.0 USB Dongle Plus
Note 1: If you want to connect 1.5m USB extension cable for better signal range, click this link to buy.
Note 2: Dongle Plus is out of stock for the moment due to large market demand and it will restock soon. You can pre-order now but it may be delayed to ship until then.
SONOFF Smart Stackable Power Meter
【Connect up to 32 SPM-4Relays】One SPM-Main can be connected 32 SPM-4Relays. Each SPM-4Relay has 4 isolated channels to help you manage devices more conveniently.
【Power metering】You can monitor the power consumption by checking eWeLink App on your mobile phone. Obtaining current, voltage and power easily.
【Max. 20A/Gang】Each channel can support maximum current of 20A, no fear of high power load.
【Communicated by RS-485】The SPM-Main communicates with the SPM-4Relays through RS-485, which allows for multi-terminal and stable long-distance data transmission.
【Overload Protection】Once the overload protection is enabled, it can protect your devices from burning out.
SONOFF Smart Stackable Power Meter in stock at the half of October, you can pre-order now but it may be delayed to ship until then.
SONOFF MS01- Smart Soil Moisture Sensor
【Monitor Soil Moisture】Works with TH10/16 to monitor your plants’ soil moisture.
【DIY A Smart Watering Device】DIY your sprinkler to water automatically according to the setting moisture value.
【IP55 Waterproof 】IP55 waterproof assure you water flowers freely without taking the sensor out.
【Voice Control 】Ask your Google Assistant for humidity conveniently.
Work with AL560 to extend measure distance.
Note : We will have SONOFF MS01- Smart Soil Moisture Sensor in stock at the half of November, you can pre-order now but it may be delayed to ship until then.
Inteligent Automatic WiFi Curtain Switch Module DIY Smart Home for Roller Shutter Motor Google Home Amazon Alexa Voice Contro
Inteligent Automatic WiFi Curtain Switch Module DIY Smart Home for Roller Shutter Motor Google Home Amazon Alexa Voice Contro
SONOFF POWR3 High Power Smart Switch
【25A/5500W Highest Output Power】POWR3 has the highest output power to make your high-powered devices smart, or as a single room-meter to measure power consumption.
【Measuring Power Consumption】Keep track of active power, current and voltage of your appliances on App
【Overload protection】Once an abnormality was detected, the power will be cut off to avoid device damage and danger.
【One-tap switch on/off remotely】POWR3 can cut off power wherever you are that can ensure the safety of your appliances and save on hidden electricity bills
【Voice Control】Compatible with Amazon Alexa, Google Assistant, SmartThings, and Alice. Just speak out your command, the smart device can do on/off as you say.
Smart Wifi Black wall touch Modular switch with Smart Home edge 4 Gang works with Alexa IFTTT,Google
Smart Wifi Black wall touch Modular switch with Smart Home edge 4 Gang works with Alexa IFTTT,Google
Smart WiFi Smart Touch Panel Dimmer Light Switch 2 Gang Modular switch works with Alexa ,Google
Smart WiFi Smart Touch Panel Dimmer Light Switch 2 Gang Modular switch works with Alexa ,Google
SONOFF DW2-RF – 433MHZ RF Wireless Door/Window Sensor
Note: SONOFF DW2-RF doesn’t come with batteries into package, and it requires gateway like SONOFF 433MHz RF Bridge to use.
Click to view the difference among DW2-RF, DW2-WiFi and SNZB-04
Household Oxygen Inhaler | Mini Oxygen Pressure Regulator | G5/8-14 Male Thread Oxygen Pressure Reducing Valve Accurate Flow Oxygen Meter for Oxygen Inhalation
Household Oxygen Inhaler | Mini Oxygen Pressure Regulator | G5/8-14 Male Thread Oxygen Pressure Reducing Valve Accurate Flow Oxygen Meter for Oxygen Inhalation
Powertip PC1602F-B Alphanumeric LCD Display 16×2
SONOFF MINIR2 – Two Way Wi-Fi Wireless Smart DIY Switch Turn traditional switch to Smart WiFi Switch With Timer Internet Work With AMAZON Alexa,google Home ,Nest
SONOFF MINIR2 – Two Way Wi-Fi Wireless Smart DIY Switch Turn traditional switch to Smart WiFi Switch With Timer Internet Work With AMAZON Alexa,google Home ,Nest
Home Portable Intelligent Oxygen Concentrator Generator machine Infrared Remote Control1-7L
Home Portable Intelligent Oxygen Concentrator Generator machine Infrared Remote Control1-7L
Complete plastic outer shell, safe and reliable.
SONOFF Motion Sensor BASE For SONOFF SNZB-03/PIR3 Universal Joint
Motion Sensor BASE, Suitable for SONOFF SNZB-03 and SONOFF PIR3.
With the universal joint, the sensor can be flexible to rotate a full 360°horizontal angle and 90°vertical angle which allows you to adjust the sensor into an optimal angle to view everything in your home (The sensor doesn’t move on its own based on your motion). Another convenience for your home is that you can use the sensor for a position where the movement is not easy to be detected via mounting it in the universal joint, and just rotate the universal joint head to get a wonderful detecting angle.
Hospital Portable Intelligent Oxygen flow/purity Concentrator Generator machine 5L
MCU Intelligent control
Real-time oxygen concentration detection
24 hours no-stop working
Practical patented technology
one-piece housing shell
Multipurpose :Atomization /with Ventilator
Intelligent alarm system : Low oxygen flow/purity ,overload , power failure
Multicolor RBG Smart LED Light Strip SONOFF L1 Lite – 5M Work with Alexa and Google Home hands-free voice control
Multicolor RBG Smart LED Light Strip SONOFF L1 Lite – 5M Work with Alexa and Google Home hands-free voice control
Note:
1. L1 lite is not water-proof, don’t use it outdoors. If need waterproof light strip, move to SONOFF L1.
2. To make it extendable, you can control multiple light strips using grouping feature
Home Portable Intelligent Oxygen Concentrator Generator machine Infrared Remote Control 7L
Home Portable Intelligent Oxygen Concentrator Generator machine Infrared Remote Control 7L
Complete plastic outer shell, safe and reliable.
Wireless WiFi LPG Gas Detector Alarm Leakage Sensor Natural,PROPANE Gas Leak Detector Alarm APP Control
Wireless WiFi LPG Gas Detector Alarm Leakage Sensor Natural,PROPANE Gas Leak Detector Alarm APP Control
1. LCD Screen Clearly Shows: Easy-to-read and clearly digital display shows combustible gas concentration and WiFi signal.
2. Natural Gas & LGP Detect: Detect the natural gas (Methane) and LPG (Liquefied Petroleum Gas) leakage
3. 85dB Alarm Sound & APP notification
4. WiFi connection, smart APP remote control. With manually test, manually mute. To temporarily mute the alarm in the gas alarm state.
5. New Design and Easy-to-install
SONOFF Zigbee 3.0 USB Dongle Plus
Note 1: If you want to connect 1.5m USB extension cable for better signal range, click this link to buy.
Note 2: Dongle Plus is out of stock for the moment due to large market demand and it will restock soon. You can pre-order now but it may be delayed to ship until then.
SONOFF Smart Stackable Power Meter
【Connect up to 32 SPM-4Relays】One SPM-Main can be connected 32 SPM-4Relays. Each SPM-4Relay has 4 isolated channels to help you manage devices more conveniently.
【Power metering】You can monitor the power consumption by checking eWeLink App on your mobile phone. Obtaining current, voltage and power easily.
【Max. 20A/Gang】Each channel can support maximum current of 20A, no fear of high power load.
【Communicated by RS-485】The SPM-Main communicates with the SPM-4Relays through RS-485, which allows for multi-terminal and stable long-distance data transmission.
【Overload Protection】Once the overload protection is enabled, it can protect your devices from burning out.
SONOFF Smart Stackable Power Meter in stock at the half of October, you can pre-order now but it may be delayed to ship until then.
SONOFF MS01- Smart Soil Moisture Sensor
【Monitor Soil Moisture】Works with TH10/16 to monitor your plants’ soil moisture.
【DIY A Smart Watering Device】DIY your sprinkler to water automatically according to the setting moisture value.
【IP55 Waterproof 】IP55 waterproof assure you water flowers freely without taking the sensor out.
【Voice Control 】Ask your Google Assistant for humidity conveniently.
Work with AL560 to extend measure distance.
Note : We will have SONOFF MS01- Smart Soil Moisture Sensor in stock at the half of November, you can pre-order now but it may be delayed to ship until then.
Inteligent Automatic WiFi Curtain Switch Module DIY Smart Home for Roller Shutter Motor Google Home Amazon Alexa Voice Contro
Inteligent Automatic WiFi Curtain Switch Module DIY Smart Home for Roller Shutter Motor Google Home Amazon Alexa Voice Contro
SONOFF POWR3 High Power Smart Switch
【25A/5500W Highest Output Power】POWR3 has the highest output power to make your high-powered devices smart, or as a single room-meter to measure power consumption.
【Measuring Power Consumption】Keep track of active power, current and voltage of your appliances on App
【Overload protection】Once an abnormality was detected, the power will be cut off to avoid device damage and danger.
【One-tap switch on/off remotely】POWR3 can cut off power wherever you are that can ensure the safety of your appliances and save on hidden electricity bills
【Voice Control】Compatible with Amazon Alexa, Google Assistant, SmartThings, and Alice. Just speak out your command, the smart device can do on/off as you say.
Smart Wifi Black wall touch Modular switch with Smart Home edge 4 Gang works with Alexa IFTTT,Google
Smart Wifi Black wall touch Modular switch with Smart Home edge 4 Gang works with Alexa IFTTT,Google
Smart WiFi Smart Touch Panel Dimmer Light Switch 2 Gang Modular switch works with Alexa ,Google
Smart WiFi Smart Touch Panel Dimmer Light Switch 2 Gang Modular switch works with Alexa ,Google
SONOFF DW2-RF – 433MHZ RF Wireless Door/Window Sensor
Note: SONOFF DW2-RF doesn’t come with batteries into package, and it requires gateway like SONOFF 433MHz RF Bridge to use.
Click to view the difference among DW2-RF, DW2-WiFi and SNZB-04
Household Oxygen Inhaler | Mini Oxygen Pressure Regulator | G5/8-14 Male Thread Oxygen Pressure Reducing Valve Accurate Flow Oxygen Meter for Oxygen Inhalation
Household Oxygen Inhaler | Mini Oxygen Pressure Regulator | G5/8-14 Male Thread Oxygen Pressure Reducing Valve Accurate Flow Oxygen Meter for Oxygen Inhalation
Powertip PC1602F-B Alphanumeric LCD Display 16×2
SONOFF MINIR2 – Two Way Wi-Fi Wireless Smart DIY Switch Turn traditional switch to Smart WiFi Switch With Timer Internet Work With AMAZON Alexa,google Home ,Nest
SONOFF MINIR2 – Two Way Wi-Fi Wireless Smart DIY Switch Turn traditional switch to Smart WiFi Switch With Timer Internet Work With AMAZON Alexa,google Home ,Nest
Home Portable Intelligent Oxygen Concentrator Generator machine Infrared Remote Control1-7L
Home Portable Intelligent Oxygen Concentrator Generator machine Infrared Remote Control1-7L
Complete plastic outer shell, safe and reliable.
SONOFF Motion Sensor BASE For SONOFF SNZB-03/PIR3 Universal Joint
Motion Sensor BASE, Suitable for SONOFF SNZB-03 and SONOFF PIR3.
With the universal joint, the sensor can be flexible to rotate a full 360°horizontal angle and 90°vertical angle which allows you to adjust the sensor into an optimal angle to view everything in your home (The sensor doesn’t move on its own based on your motion). Another convenience for your home is that you can use the sensor for a position where the movement is not easy to be detected via mounting it in the universal joint, and just rotate the universal joint head to get a wonderful detecting angle.
Hospital Portable Intelligent Oxygen flow/purity Concentrator Generator machine 5L
MCU Intelligent control
Real-time oxygen concentration detection
24 hours no-stop working
Practical patented technology
one-piece housing shell
Multipurpose :Atomization /with Ventilator
Intelligent alarm system : Low oxygen flow/purity ,overload , power failure
Multicolor RBG Smart LED Light Strip SONOFF L1 Lite – 5M Work with Alexa and Google Home hands-free voice control
Multicolor RBG Smart LED Light Strip SONOFF L1 Lite – 5M Work with Alexa and Google Home hands-free voice control
Note:
1. L1 lite is not water-proof, don’t use it outdoors. If need waterproof light strip, move to SONOFF L1.
2. To make it extendable, you can control multiple light strips using grouping feature
Home Portable Intelligent Oxygen Concentrator Generator machine Infrared Remote Control 7L
Home Portable Intelligent Oxygen Concentrator Generator machine Infrared Remote Control 7L
Complete plastic outer shell, safe and reliable.
Wireless WiFi LPG Gas Detector Alarm Leakage Sensor Natural,PROPANE Gas Leak Detector Alarm APP Control
Wireless WiFi LPG Gas Detector Alarm Leakage Sensor Natural,PROPANE Gas Leak Detector Alarm APP Control
1. LCD Screen Clearly Shows: Easy-to-read and clearly digital display shows combustible gas concentration and WiFi signal.
2. Natural Gas & LGP Detect: Detect the natural gas (Methane) and LPG (Liquefied Petroleum Gas) leakage
3. 85dB Alarm Sound & APP notification
4. WiFi connection, smart APP remote control. With manually test, manually mute. To temporarily mute the alarm in the gas alarm state.
5. New Design and Easy-to-install
Home Entertainment
SONOFF Zigbee 3.0 USB Dongle Plus
Note 1: If you want to connect 1.5m USB extension cable for better signal range, click this link to buy.
Note 2: Dongle Plus is out of stock for the moment due to large market demand and it will restock soon. You can pre-order now but it may be delayed to ship until then.
SONOFF Smart Stackable Power Meter
【Connect up to 32 SPM-4Relays】One SPM-Main can be connected 32 SPM-4Relays. Each SPM-4Relay has 4 isolated channels to help you manage devices more conveniently.
【Power metering】You can monitor the power consumption by checking eWeLink App on your mobile phone. Obtaining current, voltage and power easily.
【Max. 20A/Gang】Each channel can support maximum current of 20A, no fear of high power load.
【Communicated by RS-485】The SPM-Main communicates with the SPM-4Relays through RS-485, which allows for multi-terminal and stable long-distance data transmission.
【Overload Protection】Once the overload protection is enabled, it can protect your devices from burning out.
SONOFF Smart Stackable Power Meter in stock at the half of October, you can pre-order now but it may be delayed to ship until then.
Laptops & Computers
Trending Products
Bestseller
Top Categories of this Month
Recently Viewed
SONOFF Zigbee 3.0 USB Dongle Plus
Note 1: If you want to connect 1.5m USB extension cable for better signal range, click this link to buy.
Note 2: Dongle Plus is out of stock for the moment due to large market demand and it will restock soon. You can pre-order now but it may be delayed to ship until then.
SONOFF Smart Stackable Power Meter
【Connect up to 32 SPM-4Relays】One SPM-Main can be connected 32 SPM-4Relays. Each SPM-4Relay has 4 isolated channels to help you manage devices more conveniently.
【Power metering】You can monitor the power consumption by checking eWeLink App on your mobile phone. Obtaining current, voltage and power easily.
【Max. 20A/Gang】Each channel can support maximum current of 20A, no fear of high power load.
【Communicated by RS-485】The SPM-Main communicates with the SPM-4Relays through RS-485, which allows for multi-terminal and stable long-distance data transmission.
【Overload Protection】Once the overload protection is enabled, it can protect your devices from burning out.
SONOFF Smart Stackable Power Meter in stock at the half of October, you can pre-order now but it may be delayed to ship until then.
SONOFF MS01- Smart Soil Moisture Sensor
【Monitor Soil Moisture】Works with TH10/16 to monitor your plants’ soil moisture.
【DIY A Smart Watering Device】DIY your sprinkler to water automatically according to the setting moisture value.
【IP55 Waterproof 】IP55 waterproof assure you water flowers freely without taking the sensor out.
【Voice Control 】Ask your Google Assistant for humidity conveniently.
Work with AL560 to extend measure distance.
Note : We will have SONOFF MS01- Smart Soil Moisture Sensor in stock at the half of November, you can pre-order now but it may be delayed to ship until then.
Inteligent Automatic WiFi Curtain Switch Module DIY Smart Home for Roller Shutter Motor Google Home Amazon Alexa Voice Contro
Inteligent Automatic WiFi Curtain Switch Module DIY Smart Home for Roller Shutter Motor Google Home Amazon Alexa Voice Contro
SONOFF POWR3 High Power Smart Switch
【25A/5500W Highest Output Power】POWR3 has the highest output power to make your high-powered devices smart, or as a single room-meter to measure power consumption.
【Measuring Power Consumption】Keep track of active power, current and voltage of your appliances on App
【Overload protection】Once an abnormality was detected, the power will be cut off to avoid device damage and danger.
【One-tap switch on/off remotely】POWR3 can cut off power wherever you are that can ensure the safety of your appliances and save on hidden electricity bills
【Voice Control】Compatible with Amazon Alexa, Google Assistant, SmartThings, and Alice. Just speak out your command, the smart device can do on/off as you say.
Smart Wifi Black wall touch Modular switch with Smart Home edge 4 Gang works with Alexa IFTTT,Google
Smart Wifi Black wall touch Modular switch with Smart Home edge 4 Gang works with Alexa IFTTT,Google
Smart WiFi Smart Touch Panel Dimmer Light Switch 2 Gang Modular switch works with Alexa ,Google
Smart WiFi Smart Touch Panel Dimmer Light Switch 2 Gang Modular switch works with Alexa ,Google
SONOFF DW2-RF – 433MHZ RF Wireless Door/Window Sensor
Note: SONOFF DW2-RF doesn’t come with batteries into package, and it requires gateway like SONOFF 433MHz RF Bridge to use.
Click to view the difference among DW2-RF, DW2-WiFi and SNZB-04
Household Oxygen Inhaler | Mini Oxygen Pressure Regulator | G5/8-14 Male Thread Oxygen Pressure Reducing Valve Accurate Flow Oxygen Meter for Oxygen Inhalation