Choose it for
Light emergency backup, short trips and users who want more reserve than ES270.
5-year official-site warranty30-day returnsFree U.S. shippingDirect support
Compact CPAP backup power
ES400 AIR
A 148Wh reserve for light outages and travel plans that allow an airline-approval route.
4.19500$161.99$179.99Save $18.00
- Capacity
- 148Wh
- Chemistry
- Lithium-ion
- Planning range
- 1–2 nights
Why ES400 AIR fits this backup plan
- 148Wh compact reserve
More margin than ES270 while remaining easier to carry and store than the larger multi-night platforms.
- Plan airline approval early
A 148Wh battery can require advance airline approval. Confirm the carrier and route before travel.
- Selectable CPAP output
Match 12V, 16V, 19V or 24V to the original CPAP adapter label before connection.
- Four documented CPAP cables
Keep the correct machine-specific cable with the battery as one tested kit.
- Wall, vehicle and solar routes
Recharge planning can follow the trip instead of depending on a single power source.
- Pass-through support
Use a tested full setup when continuous backup through a charging interruption matters.
Free U.S. shippingOfficial-site orders include 30-day returns under the posted policy.
Confirm these 3 details first
- Your exact CPAP model, not only the brand or series
- The output voltage printed on its original power adapter
- Whether humidification and heated tubing will remain on overnight
Product specificationsThe details that affect fit, charging and use
- Capacity
- 148Wh
- Battery chemistry
- Lithium-ion
- CPAP DC output
- 12V / 16V / 19V / 24V selectable
- Recharge routes
- Wall, vehicle and compatible solar charging
- Pass-through use
- Supported; test the complete setup before relying on it
- Passenger air travel
- 148Wh normally requires advance airline approval; confirm before departure
Runtime & compatibilityPlan with your machine and normal bedtime settings
The planning range assumes humidification and heated tubing are off and is not a guarantee. Runtime changes with the CPAP model, pressure, mask leak, room temperature, battery condition and comfort settings. Confirm the cable and voltage, then run one complete overnight test.
What’s includedBattery, charging equipment and model-specific cables
- 1 × ES400 AIR CPAP battery
- 1 × AC charging adapter
- 4 × CPAP DC cables
- 1 × carrying bag
- 1 × user manual
Use the cable and output voltage specified for your exact CPAP model.
Warranty, shipping & returnsCoverage, delivery timing and return terms
Purchases from easylonger.com include a 5-year warranty. Purchases from other authorized platforms include 3 years and can be registered on our website to upgrade eligible coverage to 5 years. Free shipping is available to eligible U.S. addresses, and eligible orders may be returned in their original packaging within 30 days of receipt; approval and return-shipping terms apply.
Manual & product supportDocuments, setup guidance and direct help
Open the model-specific support workspace for setup videos, connection guidance and the current manual. If your CPAP is not listed, send the adapter label and machine model to support before ordering.
148WhLight backup
Up to 1–2 nights*With comfort heat off
4 voltages12V · 16V · 19V · 24V
5 yearsOfficial-site warranty
Why this model exists
Add useful overnight reserve without moving to the largest battery.
ES400 AIR gives light-backup users more margin than a travel battery while staying easier to carry and store. Confirm the CPAP, cable and voltage before the first night.
Check my CPAP
Confirm first
Check the exact CPAP voltage and whether your setup uses direct DC or a documented inverter route.
Plan the margin
Heat, humidification and pressure can reduce the number of hours available.
Inside the product
Start with the controls and connections that change the setup.
See the product system before comparing runtime or finish.
Real-use scenes
Plan how the complete kit moves.
Keep the battery, correct cable and charging route together between home, road and campsite.
Exact CPAP fit
Confirm the machine before estimating the night.
Check the full model, original-adapter voltage and documented cable before connection.
Runtime by CPAP model
Plan around the machine and settings you actually use.
Pressure, humidification, heated tubing, leaks, temperature and battery condition can change runtime.
Overnight use
Build the complete backup route before bedtime.
Placement, ventilation, pass-through use and comfort settings should be tested together.
Recharge planning
Know where the next full charge comes from.
Prepare the documented wall, vehicle, USB-C or compatible solar route before it is needed.
Tech specs
The details needed to reject or confirm the fit.
Specifications should reduce uncertainty, not become a wall of numbers.
Battery and runtime +
- Capacity
- 148Wh
- Typical planning range
- 1–2 nights
- Chemistry
- Lithium-ion
- Comfort heat
- Runtime is reduced when enabled
Output and CPAP connection +
- Direct DC
- 12V / 16V / 19V / 24V
- USB
- USB-C and USB-A
- Connection
- Model-specific documented cable
Travel and support +
- Travel planning
- Advance airline approval may be required
- Warranty
- 5 years for official-site purchases
- Returns
- 30-day free returns
Real owner setups
See how ES400 AIR is actually placed and connected.
These are customer-submitted setup photos, not studio renders. They help you notice the machine, cable route and bedside space before building your own setup.
Real CPAP routines
Real CPAP routines are more useful than generic praise.
★★★★★4.8 current-store ratingLive verified reviews belong at the point of decision.
The useful review explains the machine, cable, pressure and comfort settings—not only a star rating.
A tested night gives more confidence than a capacity claim without the assumptions.
Clear product support matters when the battery is part of an outage or travel plan.
Can selecting the wrong voltage during setup damage my CPAP?
Not while the CPAP is still disconnected. You can cycle through the voltage choices during setup without sending power to the CPAP. Stop at the voltage printed on the original adapter before connecting the cable. If the wrong voltage was selected, disconnect the CPAP, exit voltage mode and reset the output before reconnecting.
Can I use pass-through charging overnight?
Pass-through availability and the permitted charger depend on the exact ES400 AIR manual. When the manual permits it, power travels from the charger through the battery to the CPAP; it does not bypass the battery. Keep the battery ventilated and test the complete setup before relying on it overnight.
How many nights can I expect?
Use the product planning range with humidification and heated tubing off as a starting point. Pressure, leakage, CPAP model, temperature and battery condition change the result.
How do I know which cable my CPAP needs?
Match the complete CPAP model and adapter voltage in the compatibility guide. Connector shape alone is not enough.
What should I test when it arrives?
Charge fully, verify voltage and cable, then run one complete night using the settings you plan to rely on.
What purchase protection is included?
Purchases from easylonger.com include a 5-year warranty. Purchases from other authorized platforms include 3 years and can be registered on our website to upgrade eligible coverage to 5 years. Lifetime product support, 30-day free returns and free U.S. shipping apply to eligible official-site orders.
Free U.S. shippingNo hidden shipping threshold.
30-day free returnsTest the complete setup.
Warranty & registrationAutomatic for official-site orders.
Lifetime supportProduct help when the setup changes.