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HEART RATE IS ONLY HALF THE STORY

TAKE CHARGE OF YOUR HEART HEALTH
The Frontier X2 is a game changer! Worn directly over your heart, this smart heart wearable provides you with continuous heart monitoring that keeps you updated with the performance of your heart. With real-time vibration alerts, this device enables optimised training within pre-set limits. The Frontier X2 also provides accurate measurements of breathing rate thus determining how much effort you’re expending, making it suitable for all sports, including swimming!

The challenge with Heart Monitor watches and handheld devices is that they can capture your HR only when you are still for 30 seconds. What you need is a product that captures high-quality overall heart metrics continuously on your chest while you exercise and are pushing your heart the hardest.
Suitable for all Endurance Sports!

The Choice of Pro-athletes
PAULA RADCLIFFE
Former Women’s Marathon World Record Holder

Exercise with Confidence
Get real-time feedback on your heart health when you are pushing yourself the hardest, and record high-quality heart metrics while exercising.

Train Hard, Train Safe
Set discreet real-time vibration alerts for Heart Rate, Breathing Rate, and Strain and tailor your workouts to achieve personal training goals and better heart health.

Avoid overstraining your heart!
Do your workouts reassured that you are in a zone that is not overstraining your heart. Use vibration alerts to nudge your heart into a zone that will help protect and strengthen it.
Measure What Matters

The challenge with Heart Monitor watches and handheld devices is that they can capture your HR only when you are still for 30 seconds. What you need is a product that captures high-quality overall heart metrics continuously on your chest while you exercise and are pushing your heart the hardest.
Accurately monitor your heart for up to 24hrs during any activity (including sleep).
Spot changes In your wellness metrics with Al generated markers.
Avoid overstraining your heart by combining your HR with Strain.
Train in the right zone without distractions with real-time, Personalised, and discreet vibration alerts.
Add health event tags to help you understand how lifestyle choices and behaviour affect your heart health.
Accurately assess your true effort with our proprietary Breathing Rate algorithm.
Share your heart data & other metrics instantly and securely with anyone across the world.
Simultaneously connect to upto 2 external HRM devices that use Bluetooth Low Energy/Bluetooth Smart.
AI enabled wellness algorithms – Receive post-activity training insights, recommendations, and weekly goals.
Technical Specifications:
Waterproof Sweat-proof and Waterproof up to 1.5 meters Connectivity Bluetooth 5.0 for 3X speed and greater range Battery Up to 24 hours of continuous use Single Button Single blue button for all key actions Apps Available for iOS, Apple Watch and Android Phones Third Party Integrations Uses BLE Technology to connect with Garmin, Peloton or other devices Rating IP67 AI enabled Wellness algorithms Receive post-activity training insights and recommendations Weight 23 Grams Dimensions 73mm x 24mm x 13mm Charge Full charge in under 45 minutes Box Contents Frontier X2, 1 x Elastic Chest Straps, Micro USB Cable, Quick Start Guide Package Weight 260 grams Chest Strap Lightweight device snaps on to the chest belt with ease. Performance Breathing Rate, Training Load, Body Shock, Step Cadence
24/7 CONTINUOUS HEART HEALTH MONITORING: Provides continuous heart rate Monitoring, Breathing Rate, and Strain Monitoring for athletes, fitness enthusiasts, and health-conscious users—including during sleep and recovery
REAL-TIME VIBRATION ALERTS & TRAINING ZONES: Stay in your optimal heart zone with custom alerts for heart rate, breathing rate, and strain. Continuous heart rate monitoring prevents over-exertion or under-training, helping athletes and wellness users train safely and effectively.
PRO-LEVEL ACCURACY & ANALYTICS: Syncs with the Fourth Frontier app and web dashboard to record heart health metrics (Strain, HRV, Training Load, etc.). Share data instantly with coaches or doctors.
BLUETOOTH WEARABLE WITH APP/DEVICE COMPATIBILITY: Pairs via Bluetooth 5.0 (3× faster) to most fitness devices and phones. Works with iOS/Android apps, Apple Watch, Garmin, Peloton, Zwift, and more. Stream and review data live or later for in-depth training feedback.
ATHLETE-READY, WATERPROOF DESIGN: Comfortable elastic chest strap (with silicone dots) for a secure fit during any activity. Fully waterproof up to 1.5m—ideal for running, cycling, swimming, rowing, or gym workouts. Includes 1-year warranty for peace of mind.
12 reviews for Frontier X2 Smart Heart Rate Monitor Chest Strap, Wearable Heart Rate Monitor with Strain, Breathing Rate, Real Time Vibration Alerts and 20+ Fitness Activities with Continuous Heart Monitoring
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$49.99

Amazon Customer –
Pacemaker Compatible
I have a pacemaker and tried several different heart rate monitors and they all failed, including the Polar H-10, before I bought the Fourth Frontier X2. Further research revealed a paced heart has a different ECG than an unpaced heart, and the algorithms used are incompatible with a paced heart. I experience some data drops with the X2 but that is due to my pacemaker, not the X2. I still get good enough data that I know what my heart is doing. If you have a pacemaker this is well worth the cost.
Reddy –
My doctor accepts the report
The Frontier X2 works amazingly well, especially if you need some of its key features. As an example, it allows you to send your doctor a ECG trace which is a very important feature. Frontier X2 is a great choice for people concerned about their heart health. It’s not a medical device but it gives you all the data which is required to measure your heart health such as EKG monitoring, Heart Rhythm, Heart Strain etc…Frontier X2 work well for recording HRV over the course of a full day and even during sleep. You get the full ECG recording. It gives you 24 hours continuous EKG monitoring which makes it the only device with Continuous Heart Monitoring Feature.Fourth Frontier keeps on updating firmware to address problems if any. For Rebooting, You have to press and hold the button long enough to get a forced reboot in order to start the device.Finally, Kudos to Fourth Frontier Customer Support team. They are available 24*7 to address your queries.
Zachary Rosenbaum –
Good hardware but bad software and usability
Pros:1) Accuracy is better than average monitors, especially for spikes in heart rate.Cons:1) Doesn’t work correctly without internet, while you can see a live view of statistics, it won’t be able to start a new activity recording.2) It’s stingy on data, for example it might rate your HRV and give you a number, but its a rather useless number without providing a reference distribution for this instrument3) Doesn’t use usb-c.4) Some of its functionality is blocked behind a rather expensive paywall.
andres jimenez –
excelente producto
buena herramienta de control de salud
Sci Guy –
Great resource for those with AF
As an athlete having had two ablations for AF, this is a primary source for gathering all my HR workout data. While my Garmin can capture AF if I stop, remain still, use two fingers on the bezel, and think pleasant thoughts for 30 seconds…this Frontier monitor continues to capture HR data even if I am not aware there are erroneous rhythms. This can be an invaluable source of information if a significant event occurs. After eight months of nearly daily use, the unit has been flawless. While the accuracy may not be at the research level, it does provide good, accurate, long-view trends.My only complaint are the number of features it can measure vs. having to pay for a “premium” level subscription in order to view them.
Stacy –
UPDATED REVIEW
I’m updating my review for this product. I have had some interaction with customer service and used the device.First: I was extremely unhappy that the device did not come with a wall charger, considering the price tag. On top of that, they aren’t clear that it doesn’t come with the charger until you read the directions, and they state that you should use a charger that has an input of no more than 5V and output of no more than .5A. The directions caution that using a more powerful charger can damage the equipment. Well, finding a charger that lets out a trickle of power is extremely difficult (I found just one on Amazon).Customer Service: I contacted customer service during the Christmas holidays, and heard back pretty quickly after Christmas was over. They offered to reimburse my charger purchase. They also bumped my question about the charger up the line, and I was told that I could use a regular charger. I bought the low-power one and was reimbursed right away. Customer service was very attentive and polite. In all honesty, that’s rare these days, so I was very pleased about that.On to the device. I’m fairly sure the device I received was simply a lemon, based on the many reviews I’ve read. The short version is this: I tried the device for some short time periods and it seemed to work fine. Anything longer, though, and it would show that it was working but not show that it had made an activity file. I scoured the documentation for answers, tried synching the device (it would not synch), tried forcing an upload, and nothing. Eventually I got a message stating that the device memory was full, while the activity log said it had recorded just 2 hours of activity. I also had trouble with the phone app showing low or 0% battery when the device had memory in the double digits, and I had to reboot the device to get it to reconnect properly.The documentation on this is scant. It tells you how to use it (for the most part) but the troubleshooting guide read like a sales pitch rather than real help. I looked for answers in the community but found questions like mine and no answers.Customer service, again: I contacted their chat support and they were unable to help me. Instead, they asked me to set up an appointment for a video chat for onboarding. The calendar dates/times they sent were almost all in the early morning hours (from 1 AM onward) and I couldn’t find a time until the following week. They then sent me an link to a calendar for tech support, with the same kinds of times. I was able to set up a meeting for 11:30 AM on Saturday. That turned out to be 11:30 *PM*, so I was all alone in the morning and missed the evening meeting. I didn’t make a mistake. I was shocked that their tech support hours started at 1 AM my time and assumed it was because it’s an international company, so I scheduled the time best for me. I would never have scheduled an appointment for 11:30 pm.So I gave up and returned the monitor as defective. Customer service has continued to reach out to talk with me, but I’m just not interested anymore.I will say that the device does look pretty cool, and it was great fun to watch my ecg readings scroll by. The strap was surprisingly comfortable, even though I had to tuck it under my bra to have it in the right place. Do watch the videos, because I learned more about how to wear and use the device from them than from the written guides.I was looking for the device for medical purposes, and I will say that this is definitely geared toward athletes more than medical – most of the activity types were things like running and walking. But that’s ok. I don’t like that my information goes to the cloud instead of, say, to my computer, but I could live with that as well. I’ve I’d have been able to get it to work for me, I’d have used it to try to improve my heart health as well. But alas, I was not lucky.
tina –
BEST option for ECG chest straps
for $599 it’s pricey as hell, but works as it should. it has a live sharing ecg function to show to anyone with the link (link will stay the same every use) which is nice for if you make video content. shows different findings. without the yearly subscription of $119 per yr (they have monthly to), you don’t get too much. with the subscription service they provide the VO2 max to it, but no heart ecg interp. of final findings (a-fib, sinus tachycardia, bradycardia, etc)…..
Archana –
As a long-distance runner, the Frontier X2 has been a game-changer. Unlike regular fitness trackers, it provides real-time ECG, heart rate variability, strain score, and breathing rate — all during intense workouts. I use it to monitor cardiac strain and recovery, and the data has helped me optimize my training and avoid overtraining.The chest strap is super comfortable, even on 2+ hour runs, and the battery easily lasts a full day. Syncs perfectly with the app and gives me in-depth insights post-run.If you’re serious about performance and want lab-grade data on the go, this is the device to get.
Hugues V. –
Fonctionne comme promis, mais fonctionnalités disponibles sans abonnement particulièrement réduite
Amazon Customer –
Good as fitness app and for ecg monitoring, long battery life. Pricey but worth it.
Debasish –
The ECG function is next-level—accurate, detailed, and reliable. I use it daily for both workouts and general health checks. The ability to see my real-time heart rhythm makes me much more aware of how my body reacts to different intensities. It’s helped me train more efficiently and even catch irregular patterns early. This feels less like a gadget and more like a performance partner
Amazon Customer –
This heart monitor is easy to wear and has a great number of useful features. I really like the livestream ECG feature and the ability to be able to send information to a health professional.Customer services were really good in responding promptly to my queries about how to use the device. I also had an issue regarding the Apple Watch app, but this was helpfully resolved – it was apparent to me that the company really strives to achieve excellent customer service.