Questions? 1-800-356-5221

Chat with a 5-star expert now!

Questions? 1-800-356-5221

Chat with a 5-star expert now!

  1. Home /
  2. CPAP Machines /
  3. Auto Adjusting CPAP /
  4. Philips Respironics

M Series Auto CPAP Machine with C-Flex

BY Philips Respironics  |  Item #DS500S
(124) Read Reviews

This item has been discontinued by the manufacturer.

Check out the newer model

Prescription Required for Purchase

Need Replacement Parts or Accessories? Shop now

Get Your Sleep Back

Face Sleeping

Setup is easy & takes minutes

Truck Fast

Orders ship within hours (M-F)

Arrows Rotate

Resupply items set to autopilot

Item # DS500S

Not currently in stock

Product image for M Series Auto CPAP Machine with C-Flex
Product image for M Series Auto CPAP Machine with C-Flex - Thumbnail Image #1
Product image for M Series Auto CPAP Machine with C-Flex - Thumbnail Image #2
Product image for M Series Auto CPAP Machine with C-Flex - Thumbnail Image #3
M Series Machine - Filter View (Shown With Filter Installed)
Product image for M Series Auto CPAP Machine with C-Flex - Thumbnail Image #5
Product image for M Series Auto CPAP Machine with C-Flex - Thumbnail Image #6
Product image for M Series Auto CPAP Machine with C-Flex - Thumbnail Image #7
C-Flex Introduction Part 2
Filter Installation - M Series CPAP Machine
C-Flex Introduction Part 3
C-Flex Introduction Part 4
Introduction to Sleep Apnea
Overview of CPAP Power Cords and Power Supplies
Overview of CPAP DC Cables and Batteries
Click image to expand
Product Thumbnail Image #1 Product Thumbnail Image #2 Product Thumbnail Image #3 M Series Machine - Filter View (Shown With Filter Installed) Product Thumbnail Image #5 Product Thumbnail Image #6 Product Thumbnail Image #7
1/7
Product Image for M Series Auto CPAP Machine with C-Flex - Thumbnail Image #1 Product Image for M Series Auto CPAP Machine with C-Flex - Thumbnail Image #2 Product Image for M Series Auto CPAP Machine with C-Flex - Thumbnail Image #3 M Series Machine - Filter View (Shown With Filter Installed) Product Image for M Series Auto CPAP Machine with C-Flex - Thumbnail Image #5 Product Image for M Series Auto CPAP Machine with C-Flex - Thumbnail Image #6 Product Image for M Series Auto CPAP Machine with C-Flex - Thumbnail Image #7
1/7

M Series Auto CPAP Machine

The M Series Auto is a small and feature-packed CPAP that looks more like a stylish clock radio than a CPAP.

It easily packs away in your carry on luggage, and has an incredible number of high-tech features, including the patented C-Flex comfort feature, self-adjusting pressure, and powerful clinical data features, on-board.

This model is no longer available. We suggest the DreamStation 2 Auto CPAP with Heated Humidifier as a suitable replacement for the M Series Auto. The DreamStation Auto with Humidifier bundle includes the machine and heated humidifier for one low price. The DreamStation 2 is also one of the quietest CPAP machines on the market today, operating at only 25.8 decibels.

M Series Auto CPAP Machine

The M Series Auto is a small and feature-packed CPAP that looks more like a stylish clock radio than a CPAP.

It easily packs away in your carry on luggage, and has an incredible number of high-tech features, including the patented C-Flex comfort feature, self-adjusting pressure, and powerful clinical data features, on-board.

This model is no longer available. We suggest the DreamStation 2 Auto CPAP with Heated Humidifier as a suitable replacement for the M Series Auto. The DreamStation Auto with Humidifier bundle includes the machine and heated humidifier for one low price. The DreamStation 2 is also one of the quietest CPAP machines on the market today, operating at only 25.8 decibels.

Learn More About Your New Machine

C-Flex vs. Traditional CPAP: Brown University Study

Respironics has added their easy breathing C-Flex technology to the REMstar Auto M Series. Now you can have both the comfort of auto-titrating pressure with the comfort of easy exhalation, all in one CPAP.

The REMstar Auto M Series with C-Flex is is an auto-adjusting CPAP machine which is set for a range of pressures, then seeks out and delivers the lowest level of pressure needed to keep the airway open. With CFLEX technology, not only with the pressure level vary as needed, but it will drop with each exhalation.

The auto-adjusting CPAPs were designed for patients who are unable to participate in a sleep study or whose pressure needs vary during the night according to their stage of sleep or sleep position. However, any patient will receive very comfortable therapy from this type of CPAP.

The REMstar Auto M Series CPAP with REMstar Heated Humidifier includes the following features:
  • Automatically adjusts pressure based on air-flow limitations from snoring, hypopnea or apnea events.
  • C-Flex technology offers a more comfortable way to deliver sleep therapy by giving pressure relief at exhalation. The amount the pressure is lowered is determined by one of three settings that you can adjust to your comfort. You can read more about C-Flex by clicking here:
    C-Flex Brochure
  • The component REMstar M Series Heated Humidifier integrates with the REMstar Auto M Series to become one unit with only one hose and one power cord.
  • Automatic start and stop operation.
  • Mask leak alert.
  • Automatic altitude compensation adjustment.
  • International power supply to operate on any AC current from 110 to 240 without adjustment to the machine. (An adapter may be needed to plug the CPAP into a wall outlet outside the US.)
  • Direct DC operation without the need for a DC/AC inverter, just a cable and adapter which are sold separately.
  • Two washable, reusable pollen filters are included, as well as one optional ultra-fine filter.
  • Two year manufacturer warranty against defects.

Sound Level: 31 dB

Machine Dimensions: 7.5 in L x 5 in W x 3.1 in H

Machine Weight: 2.2

Machine Warranty: 2 Years

Default Machine Settings: 4-20cm H20

Humidification Available: Yes

Humidification Type: Integrated

Exhalation Relief: Yes

Ramp Mode: Yes

DC Capable: Yes

Battery Option: Yes

Auto Altitude Adjustment: Yes

Auto Start: Yes

Auto Stop: Yes

Good For: [object Object]

CPAP.com always offers these services

  • 24 hour access to our CPAPtalk.com Support Forum
  • Learning Center for information on sleep apnea and cpap equipment
  • Consumer Purchasing Trends Reports
  • Warranty Services for all items purchased through CPAP.com
  • Insurance Compliant Invoices
  • Free Prescription Request System

Manufacturer Note

  • Philips Respironics products are for sale only to patients within the U.S. and not to other third parties or businesses.
  • All services provided by CPAP.com, including advertisement, ordering, sale, delivery, instruction, and setup of the products are performed solely by CPAP.com and independently of the manufacturer.
  • A valid prescription is required for the purchase of this product.

The optional M Series Heated Humidifier is not included with this listing but can be purchased separately.

The optional Respironics EncoreViewer Software 1.0 and card reader are not included with this listing but can be purchased separately.

Here are video instructions on how to properly install and replace your Respironics M Series reusable and disposable filters. To start, click the gray play icon below.



User Manual:

The user manual included with this machine can be viewed and downloaded here: M Series Machine.

Manufacturer Warranty
This machine comes with a 2 Year Manufacturer Warranty. CPAP.com will work with the manufacturer on your behalf if the machine needs repairs. Please follow these steps:

  • Contact us at cpap@cpap.com or 1-800-356-5221 to receive an RMA (Return Merchandise Authorization) Number before returning the equipment
  • Include a note with the machine describing the issue you are experiencing, along with your full contact information to include a return shipping address and the RMA number provided to you
  • Ship only the defective items to CPAP.com at 13235 N Promenade Blvd Stafford, TX 77477
  • Do not return accessory items such as the carry bag, hose or power cords
  • Email updates will be sent to keep you informed as the machine moves through the warranty process
  • CPAP.com will contact the manufacturer on your behalf and handle all shipping between us and the manufacturer
  • The repaired or replaced unit will be returned to you. Shipping charges may apply.

Please note: The manufacturer warranty is voided by water damage or misuse of the machine.

360
Universal Power

This system operates automatically between 110v and 240v AC. When traveling either inside or outside the USA, there are no switches to switch or fuses to change. The machine will automatically sense what voltage is needed and set itself to run on that power.

The user will need to adapt the plug that goes into the wall to fit the style of outlet socket that is being used. This is simply done with a Power Adapter Plug kit. This is the same type of plug adapter that would be used with a hair dryer or an electric shaver. World Traveler Power Adapter Plugs.

Universal 12 Volt DC Power Cord

This machine come equipped with a DC plug on the back of the unit. This allows the user to connect the CPAP to an external DC battery source. The IntelliPAP can be powered by plugging the 12volt DC Power Cord into a cigarette lighter plug. This is ideal for traveling by car, boat, or recreational vehicle that is equipped with a cigarette lighter plug.

Freedom Travel Battery

The Freedom Travel CPAP Battery is currently the best battery on the market to power your M Series machine. It makes a native connection without needing to buy an inverter or extra equipment to make it work.

CPAP.com Battery Kit with Universal 12 Volt DC Cable

The 2.5 lb CPAP.com Battery Pack is surprisingly small and lightweight. The lithium ion battery can be recharged at any discharge level without losing charge time due to battery memory loss. This battery has been approved by the United Nations and Department of Transportation as tested safe for travel. This battery kit comes with the CPAP.com battery and the 12 Volt DC Power Cord.

Respironics Battery Kit with Universal 12 Volt DC Cable

This portable battery pack is an external lead acid battery that is the ultimate in power, portability and convenience. This battery kit comes with the Respironics battery and the 12 Volt DC Power Cord (connects CPAP to cigarette lighter socket).
What does CPAP therapy do?
CPAP therapy provides a constant airflow which holds the airway open so that uninterrupted breathing is maintained during sleep. It is traditionally provided through a nasal mask that seals around the nose to maintain the pressure level.
Which CPAP masks work on which machines?

Any mask will work with any machine, with one important exception. The ResMed AirMini is only compatible with certain ResMed CPAP masks. Compatible masks for the AirMini are as follows:

  • ResMed AirFit™ N20 Nasal Mask
  • ResMed AirFit™ F20 Full Face
  • ResMed AirTouch™ F20 Full Face
  • ResMed AirFit™ P10 Nasal Pillow

When considering another CPAP, APAP or BiPAP machine from ResMed or any other manufacturer, mask compatibility extends to all brands. The AirMini uses non-standard tubing to connect the machine to the mask, and is the primary reason why other masks won't work with the AirMini. Despite this issue, many of our customers consider the AirMini to be an excellent machine.

How do I choose the machine that is right for me?
We provide our customers with many tools to make informed decisions about their machine purchases. Options include:
How can I compare different machines?
We work very hard to provide many different ways for our customers to compare products. Here are the machine product guides we have created and maintain:
  • CPAP Machine Comparison Guide. This guide stacks up every CPAP machine we sell, feature by feature. If you don't know the meaning of a feature, click the question mark for a definition. The links below will take you to the most popular CPAPs, or all CPAP machines we sell.

    Compare Most Popular CPAP Machines

    Compare All CPAP Machines

  • Auto Adjusting Machine (APAP) Comparison Guide. This guide stacks up every APAP machine we sell, feature by feature. If you don't know the meaning of a feature, click the question mark for a definition. The links below will take you to the most popular APAPs, or all APAP machines we sell.

    Compare Most Popular APAP Machines

    Compare All APAP Machines

  • BiPAP, VPAP and BiLevel Comparison Guide. This guide stacks up every BiPAP machine we sell, feature by feature. If you don't know the meaning of a feature, click the question mark for a definition. The links below will take you to the most popular BiPAPs, or all BiPAP machines we sell.

    Compare Most Popular BiPAP Machines

    Compare All BiPAP Machines
What comes with my machine?
Machines come with a six foot hose, power cord, at least one filter, and manuals. Most manufacturers include a carrying case which is designed specifically for their equipment. CPAP, APAP, and BiPAP machines do not come with a delivery system or mask. CPAP masks must be purchased separately.

To see the list of what specifically comes with each machine, you can Browse for a machine. Then on the product page, click the "Specs" tab to see a full list of what comes with the machine.

Do all CPAPs use filters?
Yes, all CPAPs use at least one filter that is usually a type of foam material and washable. Some CPAPs offer finer filtration with the addition of a disposable paper filter.

Cleaning and changing filters is the only maintenance required for a CPAP machine.

The filters are located at the back of the machine at the air intake.
Are prescriptions required for mask, machine, humidifier, and EPAP purchases?

Yes. Federal law requires we have a valid prescription on file before we ship your mask, machine, humidifier, or EPAP therapy, including Provent and Bongo RX. You will also need a prescription to purchase the Nightbalance POSA device.


We provide many easy ways to get your prescription:

  • We can request your prescription for you! When you checkout, just let us know you would like us to request your prescription, or you can log into your account to have us request your prescription.
  • Fax your prescription to our toll-free fax number: 866.353.2727, or our international fax number: 713.541.7377
  • Email your prescription to cpap@cpap.com
  • Upload your prescription in your account, under the Prescriptions Section
  • Ask your doctor to fill out our prescription form. We have both a standard prescription form and an EPAP prescription form.


For more information on prescriptions, please see our Prescription Section of the Learning Center.


What is exhalation relief?
Exhalation relief is a comfort feature which reduces the air flow at the time of exhalation, making the breathing process more natural.

The following are the different types of exhalation relief names by manufacturer.

  • Philips Respironics = C-Flex, C-Flex+, A-Flex and Bi-Flex
  • Resmed = EPR (Expiratory Pressure Relief)
  • 3B Medical = RESlex
  • Apex Medical = PVA (Pressure Variation Algorithm) Pressure Relief
  • Curative Medical = EUT (Expiratory Unloading Technology)
  • DeVilbiss = SmartFlex
  • Fisher & Paykel = SensAwake Technology
  • Human Design Medical = Z-Breathe
  • Somnetics = EZEX

Here are some machines with an exhalation relief feature:

Transcend Auto miniCPAP™ Machine with EZEX
PR System One REMStar 60 Series Auto with Bluetooth
AirSense™ 10 AutoSet CPAP Machine with HumidAir™ Heated Humidifier
+ See More
What is C-Flex?
C-Flex is a pressure relief feature that makes breathing back against CPAP pressure easier to do by reducing the pressure at the beginning of exhalation and returning to therapeutic pressure just before inhalation. Independent studies conducted by leading universities indicate that patient comfort, and therefore, patient CPAP compliance, is higher with machines that use C-Flex. C-Flex is a technology invented by Respironics, is proprietary, and is not available on other brands of CPAP machines.

An example of a machine with C-Flex technology is the DreamStation CPAP Machine.

C-Flex Easy Breathing Technology Visual Graph C-Flex Easy Breathing Technology Visual Graph
What is the difference between Bi-Flex and C-flex?
C-Flex only works at the start of an exhale. Bi-Flex works during the transition from exhalation to inhalation, the transition from inhalation to exhalation and during exhalation.

CPAP.com 100% Price Protection Guarantee

When you shop with us, we want you to be confident that you are receiving the best available price. If this items goes on sale or you spot an online or retail competitor with a lower price within seven days of your purchase, let us know, and we will credit you the difference.

"Super helpful, fast shipping, friendly assistance, great selection, I love this company."

- Verified Customer, 10/25/22

★★★★★

(124)  

Read Reviews

Compare Similar Products

Manufacturer
Philips Respironics
ResMed
ResMed
Warranty
2 Years
2 Years
2 Years
Sound Level
31 dB
27 dBA
26.6 dBA
Quiet
-
Yes
Yes

Need a personal touch?

Icon for Chat with CPAP

Chat with CPAP

Questions about a product or an existing order? Start a chat and let us help you out.

Start a chat

Icon for Call us

Call us

M-F 8am-8pm
Sat 8am-5pm (CST)

1.800.356.5221

Customer Reviews

See what other customers are saying.

Overall Rating
★★★★★
4.7 124 Reviews
5  Stars 
95
4  Stars 
20
3  Stars 
6
2  Stars 
3
1  Stars 
0
Sort By
★★★★★

Solid CPAP

Verified purchase | Feb. 17, 2010 | Verified CPAP.com Customer
The Good: 1 - This is possibly the best looking CPAP of all time. It looks much better on the nightstand than the others I've had (and I've had a few). 2 - It's a decent size for travel. 3 - The software isn't very sophisticated, but it gets the job done. 4 - It's fairly quiet. 5 - The humidifier is easy to fill. 6 - It seems to be well built. The Bad: 1 - The blue lights on the buttons are crazy bright. I had to use electrical tape to cover them up. 2 - I don't really like the feel of C-FLEX, so I turned it off. 3 - The humidifier doesn't have enough capacity and it doesn't run hot enough even on the top setting to use all of the capacity in an evening, which leaves me feeling dried out, particularly in the winter. I still haven't found an integrated humidifier in any CPAP as good as the HC150. 4 - I wish the display would provide data from the night before instead of an average over the last week. 5- The 2 cables coming out of the big power brick are a pain. I am now using a new Respironics PR One Auto as my main CPAP and I actually think it's a step back from this model in most ways (other than the fact that it can supposedly detect and treat RERAs).
Was this helpful?
(0)
(0)
★★★★★

Hsieh

Verified purchase | Feb. 05, 2010 | Verified CPAP.com Customer
good product , good service
Was this helpful?
(0)
(0)
★★★★★

Satisified with new machine and order

Verified purchase | Feb. 04, 2010 | Verified CPAP.com Customer
Just got my new M series Auto C-Pap with CFlex. Have had a Respronics machine for 9 years, decided I needed an upgrade with a better humidifier that was heated, after my recent testing, with adding more air flow. So far I'm satisfied with my new machine and it's definatly quieter than my old one.
Was this helpful?
(0)
(0)
★★★★★

Thanks to the manufacturer

Verified purchase | Jan. 25, 2010 | Verified CPAP.com Customer
M Series Auto CPAP Machine with C-Flex is very silent, comfortable and user friendly. I highly recommend this machine to all CPAP users.
Was this helpful?
(0)
(0)
★★★★★

Verified purchase | Dec. 26, 2009 | Verified CPAP.com Customer
I have used this machine and it's prior model for several years with no problems. I purchased the smaller updated unit both because it was lighter (for traveling) and because I felt I needed a backup in case the other needed to be repaired (assuming it can be, and that Respironica will still be making the parts). I use my older unit at home and take the newer unit when traveling. I choose the Auto C-FLEX model with Humidifier because experience has taught me that I need these features to be comfortable. Auto C-FLEX (with ramping) is incredibly comfortable to use, providing effortless breathing, and changed my life from the very first night I began to use it. I had apnia so bad that I simply counld not stay awake during the day, and started to nod after only an hour behind toe wheel of a car. I snored so loudly that my wife started making me sleep in another room. Life was not good. By the way, I choose the nose gear (Puritan Bennet Breeze SleepGear with Large (Green) Nasal pillows. I have found this system the most comfortable for me, allowing almost unlimited movement at night on both sides, on my back (for the firse time in years), and on my stomach (head to the side of course). The standard hose has proven to be adaquate. The filters are great, especially the micro dust and pollen filter (clean air all the time. Breathing moist air, by the way has a surprising cooling effect on vary hot nights. I have found it valuable to carry an extension cord and one extra milti outlet plug when traveling to allow machine electrical connection to plugs far away from the bed. One final comment. I have found the DC connection capability of the machine to be invaluable when camping. I purchased the DC adaptor, and attached the machine to a Marine Battery rated at 150 amp hours. The machine consumes an average of 3 amp hours (18 amp hours consumed if you sleep a 6 hour night). I re-charge the battery with an inexpensive solar unit the size of a sun visoor and have kept the system going for 2 weeks when fishing. I carry distilled water (20 oz in a Sams Club bottle) and have not run out yet durig a trip - water evaporated slowly in the humidifier. Good product, easy breathing in and out, minimum discomfort. Thanks for the high quality engineering - that such a simple thing could make such a difference in my life at the price it is offered.
Was this helpful?
(0)
(0)
★★★★★

M Series Auto CPAP Machine with C-Flex

Verified purchase | Oct. 28, 2009 | Verified CPAP.com Customer
Small compact size,easy to carry able to used with most Volatage I am happy with this machine.
Was this helpful?
(0)
(0)

Customers Also Viewed

Product image for Shielded DC Cord for PR System One 60 Series Machines
★★★★★
$29.95

Shielded DC Cord for PR System One 60 Series Machines