Both the ResMed AirMini and the Breas Z2 Auto are popular travel CPAPs known for their compact size and advanced technology. However, they have important differences that buyers should be aware of. In this review, we explore their similarities and differences in detail.

First, we’d like to give you a quick breakdown of the features of both machines in the table below. Then we’ll discuss the similarities, followed by the differences between the AirMini and the Z2 Auto in detail.

Before we dive deeper into the two travel units, we’d like to point out the most important difference between the two machines: the AirMini requires a smartphone for setting adjustments while the Z2 Auto does not. The AirMini does not have a screen or any adjustment buttons.

Simply put, if using a mobile app to adjust your CPAP therapy doesn’t appeal to you, you might want to steer away from the AirMini.

ResMed AirMini vs Breas Z2 Travel APAP Comparison Chart

ResMed AirMiniBreas Z2 Auto
Release DateMay 2017Mar 2019
Dimensions (Size)5.4 x 3.3 x 2.1 inches6.48 x 3.30 x 2.02 inches
Footprint17.82 sq inches21.39 sq inches
Weight10.6 oz10.4 oz
HumidificationProprietary HumidX & HumidX Plus Heat Moisture Exchanger (HME)Universal Heat Moisture Exchanger (HME)
Quietness (Noise level)30 dBA26 dBA
Operating Pressure Range4-20 cm H2O4-20 cm H2O
Operation ModeCPAP, APAP, APAP For HerCPAP, APAP
Power100-240V, 50-60Hz100-240V, 50-60Hz
Integrated BatteryNoYes, Optional PowerShell Module w/ Extended Battery
Ramp Time 0-45 minutes (also features AutoRamp)0-45 minutes
Mobile Device AppAirMini (Apple 4.6 stars, Android 4.4 stars)Nitelog (Apple 1.5 stars, Android 2 stars)
Altitude AdjustmentAutomatic up to 8500 Feet (2591 m)Automatic up to 8000 Feet (2438 m)
Leak CompensationYesYes
Supports Remote MonitoringYesNo
Compatible with All MasksNoYes
Expiratory Pressure ReliefYes (EPR)Yes (Z-Breathe)
Data AccessAppApp, PC software

Similarities between ResMed AirMini and Breas Z2 Auto

Size and Weight

In terms of physical characteristics, both machines weigh just over 10 oz and are roughly the size of a smartphone, albeit a large one. Both machines can easily fit inside an overnight bag, backpack and tote bag/large purse with ample room left for a mask, hose and some extra mask parts.

In fact, the AirMini held the title of the world’s smallest travel CPAP until the advent of the Transcend Micro, which is now the tiniest CPAP on the planet.


Both the AirMini and the Z2 offer waterless humidification using heat moisture exchangers (HMEs) that capture and store heat and moisture from the user’s exhaled breath, releasing them during the next inhalation to heat and humidify the air. HMEs are a great way to offer humidification without adding too much extra bulk.

It’s important to note that while both the AirMini and Z2 use HMEs for humidification, they differ in their HME setup and design. We’ll dive deeper into this when we discuss the differences between the two travel units.  

Comfort Features

Both machines offer the following comfort features:

  • Ramp
  • Pressure Relief

Ramp allows the machine to start you off on a pressure that’s lower than your prescribed therapy pressure. This lower pressure, called Ramp Pressure, then increases over a set amount of time (called Ramp Time) until it reaches the prescribed CPAP pressure. If you’re on auto CPAP mode, Ramp Pressure will increase over the set Ramp Time to your minimum pressure setting. Ramp makes falling asleep much easier and we highly recommend using this feature if you’re new to CPAP.

Both the AirMini and Breas Z2 Auto allow users to set Ramp Time in 5 minute increments up to 45 minutes. However, the AirMini has an additional AutoRamp feature that is not available on the Z2. AutoRamp is an upgraded Ramp feature that increases Ramp Pressure after the machine determines you’ve fallen asleep.

Pressure relief – called EPR on the AirMini and Z-Breathe on the Z2 – lowers pressure on exhalation, making it much easier to breathe out against the CPAP. Like Ramp, this feature helps new CPAP users acclimate to therapy. Both travel machines allow you to adjust the pressure relief level from 1 to 3. Each level corresponds to the amount of pressure decrease during exhalation. Of course, you can turn pressure relief off on both machines as well.  

Bluetooth Connectivity

Both the AirMini and Z2 Auto feature Bluetooth connectivity for sleep data monitoring on the AirMini app or the Nitelog app, if you’re using the Z2. Without getting into all the features of each mobile app, we’ll mention that while both apps lets you view your usage hours and AHI, only the Nitelog app allows you to generate a compliance report that can be printed out or emailed to your doctor.

Compliance reporting isn’t a problem for AirMini users if you have remote compliance monitoring set up with your doctor. If you don’t have remote monitoring set up, however, there is no way to generate a detailed compliance report. The AirMini app is geared towards patients and does not display detailed information such as pressure waveforms or break down the types of apneas the machine detects. If you’re required to submit compliance reports for

Other Similarities

Both machines are dual voltage (100-240V, 50-60Hz) and can be used in any country without a converter or transformer. You might need a travel plug adapter, depending on your country of destination, but plug adapters are easy to pack and relatively inexpensive.

Both units operate at a pressure range of 4-20 cm H2O and both automatically adjust for altitude (up to 8,500 ft for AirMini and up to 8,000 ft for Z2). 

Differences between the ResMed AirMini and Breas Z2 Auto

Noise Level

Perhaps because the Z2 is a newer machine (it is 2 years younger than the AirMini), its technology has allowed for quieter performance. While the AirMini is not exactly loud at 30 decibels, the Z2 operates at 26 decibels, making it the quietest travel CPAP even with the newest Transcend Micro factored in.  The Z2 also comes with a Q-Lite in-line Muffler which reduces operating noise even more.

Integrated Battery

If you’re looking to take your travel CPAP camping or anywhere without a power source, battery options are available for both the AirMini and the Z2. However, only the Z2 offers an integrated battery unit.

Breas offers an optional Powershell Battery Module for the Z2 and while it is an “integrated” module, it does not disappear in the body of the Z2. Instead, it is a battery unit that weighs an additional 15.5 ounces and is 8.25 x 4 x 3.25 inches in size. This powershell module comes with an extended life battery that offers over 8 hrs run time on CPAP pressure 20cm H2O.

ResMed AirMini vs HDM Z2 - Travel CPAP Comparison
Breas Z2 Auto Travel CPAP with Powershell and Battery

Conversely, the AirMini can be powered by a third-party battery, such as the Medistrom Pilot-24-Lite Lithium Ion Battery. No integrated battery exists for the AirMini.

Battery units for each of the machines come out to about the same amount ($350 to $450), although you may find the “integrated” unit for the Z2 somewhat more elegant. 

Heat Moisture Exchanger Setup

Earlier on, we mentioned both the AirMini and Z2 Auto use HMEs for humidification but differ in their HME setup. Now we’ll explore this in detail as it is a bit complicated and related to CPAP mask compatibility.

The AirMini uses proprietary HMEs called HumidX/HumidX Plus capsules. These HMEs are shaped like circular discs and can only be connected to the AirMini via AirMini specific ResMed CPAP masks. In other words, if you’re not using one of the AirMini specific masks, you can’t use the HumidX and HumidX Plus HME capsules.

The Breas Z2 Auto, on the other hand, uses the Z1/Z2 HME which is a traditional HME design that is compatible with all CPAP masks. You can, in fact, even use the Z1/Z2 HME with any CPAP machine, including the AirMini.

Mask Compatibility

Like all other CPAP machines on the market, the Breas Z2 Auto is compatible with all CPAP masks. The AirMini, however, is a whole different story.

ResMed designed the AirMini to only work with AirMini specific masks. Luckily, these AirMini specific masks cover all types and include nasal pillows, nasal and full face, so there is a mask for everyone. For the complete list of AirMini specific ResMed masks, check out our AirMini In-Depth Review.

Now, there is a way to use any mask with the AirMini, thanks to ingenious third party manufacturers, but note that if you go with this mask and machine setup, you cannot use the HumidX/HumidX Plus HME capsules. If you want to add some humidification, you’ll have to use a generic HME such as the Z1/Z2 HME.

To use any CPAP mask with the AirMini, you will need an AirMini adapter and a non-heated hose. The AirMini adapter lets you connect the non-heated tubing to the device so you can use your favorite mask with your AirMini.

AirMini Adapter

Data Access and Compliance Reporting

Aside from mask compatibility, another major difference between the Z2 Auto and the AirMini is data access and the subsequent ability to generate compliance reports. Z2 Auto users can access their sleep data and generate compliance reports via the Nitelog app or the Breas DataViewer PC software. The only limitation is that the PC software only supports Windows OS.

AirMini users, unfortunately, can only access their sleep data via the mobile app. There is no option to download data onto a computer as the AirMini doesn’t support an external storage device (e.g., an SD card) and doesn’t have a USB port like the Z2. As we mentioned earlier when discussing the mobile apps, the AirMini app doesn’t give users the option to generate detailed compliance reports. The app is geared towards patients and does not display detailed information such as pressure waveforms or breakdowns of the types of apneas detected by the machine. Luckily, this information is still available through the AirMini’s remote compliance monitoring system.

The ResMed AirMini’s remote compliance monitoring system allows healthcare providers to access your therapy data and make changes to your therapy settings, all without needing access to the physical machine. Providers can also generate compliance reports online at any time. The caveat is that users will have to reach out to their provider for the compliance report if they need one. If booking a doctor’s appointment just for a compliance report sounds like a headache, we invite you to take a look at our CPAP Compliance Reporting and Sleep Therapy Consultation Service. For just $49/year, our medical staff will send compliance reports and provide personalized therapy feedback based on your sleep data.

To read more about what information these compliance reports show and understand how they benefit you, check out our detailed guide on CPAP Setup, Therapy Analysis, and Sleep Consultation Service. Our Registered Polysomnographic Technologist, Anne, provides a comprehensive overview of all the information available in these compliance reports.

The Takeaway

Now that we’ve provided you with ample information about the AirMini and the Z2 Auto, we’ll offer two key factors that might help you determine your dealbreakers.

Your buying decision essentially comes down to two main points:

  1. How comfortable are you with technology?
  2. Do you want the ability to access your detailed sleep data independently?  

If you enjoy using technology and don’t find adjusting settings via a smartphone app inconvenient, the ResMed AirMini is likely more appealing. While its mask and humidification setup is more complicated, its entire setup is sleeker and more modern.

If the ability to access detailed sleep data yourself is very important to you, then the Breas Z2 Auto is the better choice. With the AirMini, you must rely on a provider to access your compliance report. There is no workaround.

We hope you found this comprehensive comparison of the ReMed AirMini and the Breas Z2 Auto informative. If you have any questions about either machines or any machine, feel free to give us a call at 866-936-3754. You can also send us an email ( or chat with us on our website.