Inogen One G4 Portable Oxygen Concentrator - Certified Pre-Owned
Inogen One G4 Portable Oxygen Concentrator - Certified Pre-Owned
Available in stock
Couldn't load pickup availability
Description
Description
Certified Pre-Owned
Introducing the smallest portable oxygen concentrator from the most popular brand, Inogen. The Inogen One G4 is capable of providing oxygen delivery in an unbelievable small and quiet package. With flow settings from 1-3, the Inogen One G4 is designed to increase independence for most users 24/7. It can be charged at home or on the go - giving you the freedom you deserve.
The Inogen One G4 delivers the independence of a portable oxygen concentrator in one of the smallest, lightest, and quietest packages available to the oxygen user today.
The Inogen One G4 provides you with 3 separate oxygen flow settings. It also includes Inogen’s Intelligent Delivery technology, which sets it apart from the competition. This innovative system rapidly detects a breath and delivers oxygen in the first 400 milliseconds. This is critical because this period is when the most gas exchange occurs in the lungs. Delivering oxygen at the start of a breath ensures that the oxygen is used more efficiently by your body.
At only 40 decibels, the G4 produces less noise than a normal indoor conversation. This means you won’t disturb others when you use your oxygen concentrator and will feel more comfortable in social settings. It’s also great in quiet environments when you want to be unobtrusive.
Furthermore, Intelligent Delivery accurately detects your breathing rate and adjusts the oxygen level provided accordingly. If you’re exercising or physically active, the unit will provide smaller, quick bursts of oxygen to satisfy your energy needs. However, during rest or sleep the system provides larger oxygen boluses more slowly to correspond with your decreased rate of respiration. This means the G4 can be effectively used during sleep at night, an area where many other portable oxygen concentrators fall short. With the G4, you won’t need separate oxygen systems for the day and night.
| SPECIFICATIONS: |
Weight
2.8 lbs
Dimensions
5.91 × 2.68 × 7.2 in (Height includes single battery)
Oxygen Flow
Intelligent Delivery Technology
Three flow settings from 1-3
Power Settings
AC Power Supply 100-240V, 50-60Hz
(auto sensing to allow worldwide use)
DC Power: for mobile use in car/airplane
Battery
Duration (single battery): up to 2.7 hours
Duration (double battery): up to 5 hours
Noise Level
40 dBA*
Warranty
Concentrator: 1 Year
| SYSTEM INCLUDES: |
- One single battery
- Concentrator
- AC/DC power supplies
Shipping & Rerturns
Shipping & Rerturns
MajorCPAP Offers Free Standard Shipping on all orders over $99 placed on our website within the Continental United States.
Shipping Services We Use:
Please Allow 1-3 Business Days For Your Order To Be Processed & Shipped. The Warehouse Is Open Monday Through Friday From 9-5. We Strive To Use The Service Which Provides Us The Fastest Shipping Option.
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
Honoring Our Veterans
As a token of our appreciation, we offer an exclusive discount to veterans.
Click below to verify and unlock your savings.
Your trusted supplier for CPAP and Oxygen equipment
Frequently asked questions
Shoot our team an email & we’ll get back to you ASAP
How long does it take to process an order?
How long does it take to process an order?
Orders are typically processed within 1–2 business days. You will receive a confirmation email with tracking details once your order has been shipped. Please note that processing times may be slightly longer during high-demand periods or sales events.
How do I know if this machine or mask will work for me?
How do I know if this machine or mask will work for me?
Every person’s needs are different. If you’re unsure, reach out to our team — we’ve helped thousands of customers find the right setup for their prescription, comfort, and breathing style. We can match your device, mask type, and pressure settings so you get the best results.
Do I need a prescription to buy a CPAP or BiPAP machine?
Do I need a prescription to buy a CPAP or BiPAP machine?
Yes. In the U.S., the FDA requires a prescription for CPAP and BiPAP machines. Masks, tubing, and most accessories can be purchased without one. If you’re unsure what you need, we can help guide you through it.
How often should I replace my mask, tubing, and filters?
How often should I replace my mask, tubing, and filters?
For best performance, replace your mask every 3 months, tubing every 6 months, and filters every 2–4 weeks (or as recommended). This keeps your therapy clean, safe, and effective.
Are your machines new or refurbished?
Are your machines new or refurbished?
We offer both brand new and certified pre-owned units. All refurbished machines are carefully inspected, sanitized, and tested to ensure they perform like new — often at a fraction of the price.
Do these machines come with a warranty?
Do these machines come with a warranty?
Yes! All new machines come with a manufacturer’s warranty, and our refurbished units include a MajorCPAP limited warranty for peace of mind. You’ll see the warranty details on each product page.
How loud are CPAP and oxygen concentrator machines?
How loud are CPAP and oxygen concentrator machines?
Most modern CPAPs run at around 25–30 decibels — about as quiet as a soft whisper. Oxygen concentrators are slightly louder, but still comfortable for home use, especially when placed a few feet away from the bed.
What’s the difference between portable and stationary?
What’s the difference between portable and stationary?
Portable concentrators are lightweight and battery-powered — great for travel or daily outings. Stationary concentrators plug in and deliver continuous oxygen, ideal for home use.
What kind of support do you offer after purchase?
What kind of support do you offer after purchase?
Our customer service doesn’t stop after checkout. We’re here to help with setup, troubleshooting, replacement parts, and warranty support — by phone, chat, or email. You’ll always talk to a real person who knows the products.
Our Brands
