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SENSZO 4-in-1 CO & Gas Detector
SENSZO 4-in-1 CO & Gas Detector
- Live CO & gas readings
- Detects CO, natural gas & propane
- Real numbers, not just a green light
- Audible alert before it's too late
- Firefighter recommended | 100-Night Trial
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PREVIOUS MONTH
Sold Out (3200 SENSZO Detectors Were Sold)
CURRENT MONTH
83% Sold (
3984
out of 4800 SENSZO Detectors)
Plug SENSZO into an outlet and give it around 200 seconds to calibrate. No tools, no ladder, and no complicated setup.
Unlike a smoke alarm, it does not need to be mounted high on the wall. Carbon monoxide mixes with the air, so simply choose the room you want to monitor, such as a bedroom, kitchen, or hallway.
Yes. We send the correct plug type based on your delivery country.
U.S. orders arrive with a U.S. plug, and UK orders arrive with a UK plug.
2 - 4 monitors are ideal for most homes. Put one near the bedrooms, one in the kitchen or living room, one near the furnace or water heater, and one on another floor.
CO (PPM) tells you how much carbon monoxide the monitor detects in the air. 0 PPM means none detected. The higher the number, the more CO is present. SENSZO alerts at 10 PPM.
Gas (%LEL) shows whether the monitor detects combustible gas in the air. 0 means none detected. A number above 0 means gas has been detected.
Temperature shows how warm the room is in °F or °C.
Humidity shows the moisture level in the air. It is shown as a percentage. Most homes are comfortable around 30–50%.
Most standard CO detectors give you a green light and only sound when they reach their alarm threshold. Many are set to alert at 70 PPM. SENSZO shows the live CO reading on screen and alerts at 10 PPM.
It also monitors combustible gas, temperature, and humidity, while most standard alarms only monitor CO. SENSZO uses Grade 3 dual sensors rather than a single Grade 1 sensor for faster, more reliable readings.
Instead of waiting for an alarm, you can check the numbers whenever you want.
What the professionals have to say.
THE DANGER YOU CAN'T SEE OR SMELL
CO can build quietly while everyone inside carries on as normal.
Carbon monoxide is invisible and has no smell. Its early effects can feel like a headache, fatigue, or the flu. In serious exposure, confusion, loss of consciousness, and death are possible.
Physical stress gets louder
Standard alarms finally react
*PPM - parts per million, showing how much carbon monoxide is present in the air.
Don't wait for someone to suffer before you act.
SENSZO puts what matters live on one clear screen, so you can check the air in your home instead of relying on a symptom or waiting for an alarm.
CAN YOU TRUST THE DETECTOR YOU ALREADY HAVE?
You have a detector. But will it work when it matters?
40% of tested home CO detectors failed to alarm at the highest hazardous levels
The average home check costs $500+. SENSZO gives you clear readings every day.
More time to notice. More time to act.
WHAT A STATUS LIGHT CAN TELL YOU
Your detector is on. That is all you know.
- Shows the unit has power
- May show a basic operating status
- Does not show live room readings
WHAT SENSZO LETS YOU SEE
What is happening in your home, right now.
- Live CO and gas readings
- Temperature and humidity
- One clear screen you can check at a glance
Find what coverage works for you
Which rooms in your home are you leaving unchecked?
Tap the rooms you want to cover
✓
THIS IS NOT A RARE ACCIDENT
It doesn't take a fire for CO to become deadly.
Carbon monoxide has no smell and no colour. The risk is believing everything is fine simply because there is no warning yet.
Americans die each year from unintentional CO poisoning not linked to fires.
Americans visit an emergency department for CO poisoning each year.
Americans are hospitalized for CO poisoning each year.
These aren't freak accidents. They happen in ordinary homes, just like yours
U.S. CDC, Carbon Monoxide Poisoning Basics, reviewed January 2026.
A firefighter's perspective
The green light was on. The family was still in danger.
I have walked into carbon monoxide calls where the alarm never sounded, the green light was still on, and the family had no idea anything was wrong. That is what made me take home protection seriously. SENSZO gives me a clear reading, not just a light that tells me to assume everything is fine.
Know what’s in the air your family breathes.
the readings explained
WHO SENSZO IS FOR
If your home burns anything, SENSZO is for you.
FAQs
Yes, SENSZO is designed to monitor carbon monoxide and combustible gas & propane in one device. It also shows temperature and humidity on the same screen.
Three to four monitors is ideal for full-home coverage. Place one near the bedrooms, one in the main living area, one near your furnace or water heater, and one on any additional floor. That covers the places you sleep, spend time, and run fuel-burning appliances.
For carbon monoxide, height is less important because CO mixes evenly with the air. Simply plug SENSZO into a suitable wall outlet. For combustible-gas monitoring, choose an outlet in the area you want to monitor and keep the screen easy to check.
The sensor is designed for up to five years of normal use. SENSZO also comes with a 100-Night Trial, so you can make sure it is right for your home.
The live display shows the current CO and combustible-gas readings on screen, along with temperature and humidity, so you can see it is actively monitoring the room.
No. Plug SENSZO into a suitable wall outlet and allow it to complete its initial calibration. No Wi-Fi, app, or battery replacement needed.
Customer Reviews
Overall rating: 5.0 / 5 from 3000 reviews.
We moved into an older house recently and this was one of the first safety upgrades I wanted to make. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. One is near the kitchen and another is close to the guest room. The screen is what makes this feel different from what we had before. It feels better suited to a normal family home than what we had before.
I wanted a detector that felt practical for a family home and not just something you plug in and forget. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. I wanted one near the utility room and one upstairs. The display gives me something concrete to look at instead of a vague status light. I did not buy it for the extras, but I have ended up liking them. It has made the house feel easier to keep an eye on.
We use propane at home, so I spent a while looking for something that felt more useful than a basic alarm. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. The hallway outside the bedrooms felt like the right place for ours. I have found myself checking the added room information more than I thought I would. We ended up feeling the bundle was the right call once everything was in place.
I bought these because my parents needed something simple that did not require a lot of explaining. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. We spread them between the main floor and the sleeping area. It feels better knowing the main spaces are covered for family visits. I like knowing the main rooms are covered in a more thoughtful way.
We have a water heater in the basement and I wanted a clearer setup throughout the house. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. Ours is near the kitchen so it is easy to check without going out of our way. It is straightforward enough for older family members to get used to. For our home, it feels like a sensible step up from what we had before.
The boiler is tucked away in a utility room and I never liked the idea of forgetting about it. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. One went near the kitchen and another near the hallway to the bedrooms. We chose the bundle after thinking through the rooms one by one. That practical visibility is exactly what I wanted from it.
Our old detector had been there for years and I was ready to replace it with something easier to understand. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. The basement one was important to me because of the water heater. As time has gone on, that visible information is the part i appreciate most day to day. For us, it is a much more useful way to think about home safety.
The guest room and hallway were what made me decide to get more than one. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. We focused on the rooms where everyone spends the most time. Those details help the device feel more relevant to everyday life. We now feel our coverage matches the way the house is actually lived in.
Our grandchildren stay over often and I wanted the main rooms to feel properly covered. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. The bundle made sense once I started thinking room by room. The screen is clear enough that I can read it quickly as I walk past. We were especially glad to have thought about the bedrooms. I am happy with the decision and would make the same choice again.
Our kitchen has a gas range and I wanted a better sense of what was going on day to day. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. I liked being able to choose sensible locations without overthinking it. I did not want a device that felt mysterious once it was plugged in. I appreciate that the screen gives a little more than the basics. It has been a reassuring change without being something we have to fuss over.
One detector did not feel like enough once we thought about the bedrooms and the main floor. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. I wanted coverage in the rooms that see the most day-to-day use. It suits the practical side of running an older house. It has been a straightforward upgrade and a worthwhile one.
We have an older gas furnace, so I wanted something clearer than our previous detector. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. We chose the living room because that is where the fireplace is. At the same time, for me, the display is the whole point because it makes the device feel more useful. That has given us a more settled feeling about the rooms we use most.
We use a fireplace through the colder months and I wanted something a bit more informative in the living room. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. We put one near the bedrooms and another in the main part of the house. It is easy to check without stopping what I am doing. The added temperature and humidity readings make it feel more complete. It feels like the kind of small improvement that genuinely makes sense.
We wanted something sensible for a house with several gas appliances. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. We put the larger bundle to use across the rooms that matter most to us. We chose the bundle after thinking through the rooms one by one. I do not think about it constantly, but I feel better knowing it is there.
My husband and I were both tired of relying on a tiny status light and hoping for the best. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. The placement ended up being very straightforward once I looked at the house properly. I like being able to glance over and actually read what is on it. It has given us the sort of reassurance we were hoping for.
We have a small cabin that uses propane and I wanted something that felt straightforward whenever we stay there. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. I placed it where I know I will actually look at it. The readout is tidy and easy to make sense of at a glance. We were especially glad to have thought about the bedrooms. The extra clarity is what makes this one stand out to me.
The main reason I ordered was that our home has two floors and I wanted coverage where people actually spend time. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. It felt better having them in visible places rather than tucked away. It feels better knowing the main spaces are covered for family visits. The whole setup now feels more in line with how we use the house.
I bought a larger bundle after realising how many important rooms we were trying to cover with one old detector. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. The upstairs landing was one of the first spots I thought about. The screen is easy on the eyes and does not feel cluttered. I have found myself checking the added room information more than I thought I would. That is what makes it feel worth having in the house.
Our son suggested getting something with a proper display and I am glad we listened. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. I placed it in the hallway where everyone passes several times a day. It suits the practical side of running an older house. I am glad we upgraded before the next family visit.
We are home more these days and pay more attention to the small things around the house. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. We put one close to the family room and one nearer the bedrooms. It is straightforward enough for older family members to get used to. I feel more comfortable having it there than I did with our old setup.
The old unit still had power, but it never told me anything useful beyond that. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. We chose the living room because that is where the fireplace is. The other part I appreciate is that for me, the display is the whole point because it makes the device feel more useful. That has given us a more settled feeling about the rooms we use most.
We wanted something easy enough that nobody in the house would put off using it. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. I liked being able to choose sensible locations without overthinking it. I did not want a device that felt mysterious once it was plugged in. The extra readouts are more useful than I expected. It has been a reassuring change without being something we have to fuss over.
I liked the idea of being able to check information instead of guessing from a coloured light. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. The hallway outside the bedrooms felt like the right place for ours. The added temperature and humidity readings make it feel more complete. We ended up feeling the bundle was the right call once everything was in place.
The hallway near the bedrooms was always the place I wanted better coverage. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. One went near the kitchen and another near the hallway to the bedrooms. We chose the bundle after thinking through the rooms one by one. That practical visibility is exactly what I wanted from it.
We use a backup generator now and then, so I wanted to feel more organised about the house overall. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. One is near the kitchen and another is close to the guest room. The screen is what makes this feel different from what we had before. It feels better suited to a normal family home than what we had before.
Our daughter and her family visit a lot, and that made me think more seriously about room coverage. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. The bundle made sense once I started thinking room by room. The screen is clear enough that I can read it quickly as I walk past. We were especially glad to have thought about the bedrooms. I am happy with the decision and would make the same choice again.
The kitchen and living room are the spaces we use most, so that is where my mind went first. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. We spread them between the main floor and the sleeping area. It feels better knowing the main spaces are covered for family visits. I like knowing the main rooms are covered in a more thoughtful way.
I was looking for something that felt calm and practical rather than technical and fussy. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. We put one near the bedrooms and another in the main part of the house. It is easy to check without stopping what I am doing. Those details help the device feel more relevant to everyday life. It feels like the kind of small improvement that genuinely makes sense.
The propane heater in our outbuilding was one of the reasons I started looking at these. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. I wanted coverage in the rooms that see the most day-to-day use. It suits the practical side of running an older house. It has been a straightforward upgrade and a worthwhile one.
It was time to replace an old setup that never gave us much confidence. Our old one only showed a green light and that always felt a bit vague to me. It was simple to plug in and get going. Ours is near the kitchen so it is easy to check without going out of our way. It is straightforward enough for older family members to get used to. For our home, it feels like a sensible step up from what we had before.
We have an older gas furnace, so I wanted something clearer than our previous detector. The previous detector did not give us much information beyond whether it had power. It was simple to plug in and get going. The basement one was important to me because of the water heater. Another thing I noticed is that that visible information is the part i appreciate most day to day. For us, it is a much more useful way to think about home safety.
Our kitchen has a gas range and I wanted a better sense of what was going on day to day. The previous detector did not give us much information beyond whether it had power. It was simple to plug in and get going. I wanted one near the utility room and one upstairs. The display gives me something concrete to look at instead of a vague status light. I appreciate that the screen gives a little more than the basics. It has made the house feel easier to keep an eye on.
We use propane at home, so I spent a while looking for something that felt more useful than a basic alarm. The previous detector did not give us much information beyond whether it had power. It was simple to plug in and get going. We focused on the rooms where everyone spends the most time. I have found myself checking the added room information more than I thought I would. We now feel our coverage matches the way the house is actually lived in.
The boiler is tucked away in a utility room and I never liked the idea of forgetting about it. The previous detector did not give us much information beyond whether it had power. It was simple to plug in and get going. We put the larger bundle to use across the rooms that matter most to us. We chose the bundle after thinking through the rooms one by one. I do not think about it constantly, but I feel better knowing it is there.
We moved into an older house recently and this was one of the first safety upgrades I wanted to make. The previous detector did not give us much information beyond whether it had power. It was simple to plug in and get going. The placement ended up being very straightforward once I looked at the house properly. I like being able to glance over and actually read what is on it. It has given us the sort of reassurance we were hoping for.
Our grandchildren stay over often and I wanted the main rooms to feel properly covered. The previous detector did not give us much information beyond whether it had power. It was simple to plug in and get going. I placed it where I know I will actually look at it. The readout is tidy and easy to make sense of at a glance. We were especially glad to have thought about the bedrooms. The extra clarity is what makes this one stand out to me.
I bought these because my parents needed something simple that did not require a lot of explaining. The previous detector did not give us much information beyond whether it had power. It was simple to plug in and get going. It felt better having them in visible places rather than tucked away. It feels better knowing the main spaces are covered for family visits. The whole setup now feels more in line with how we use the house.
We use a fireplace through the colder months and I wanted something a bit more informative in the living room. The previous detector did not give us much information beyond whether it had power. It was simple to plug in and get going. The upstairs landing was one of the first spots I thought about. The screen is easy on the eyes and does not feel cluttered. The added temperature and humidity readings make it feel more complete. That is what makes it feel worth having in the house.
One detector did not feel like enough once we thought about the bedrooms and the main floor. The previous detector did not give us much information beyond whether it had power. It was simple to plug in and get going. I placed it in the hallway where everyone passes several times a day. It suits the practical side of running an older house. I am glad we upgraded before the next family visit.
We have a water heater in the basement and I wanted a clearer setup throughout the house. The previous detector did not give us much information beyond whether it had power. It was simple to plug in and get going. We put one close to the family room and one nearer the bedrooms. It is straightforward enough for older family members to get used to. I feel more comfortable having it there than I did with our old setup.
SENSZO 4-in-1 CO & Gas Detector
SENSZO 4-in-1 CO & Gas Detector
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