Checkme O2 Max Tips: Using the Long Battery

Q: What's the long battery good for?

Trips. Record several nights away without your charger or phone. Skipping the morning sync. Useful if you don't want your phone by the bed. How many nights you get depends on your model and how much the vibration goes off. Check the manual, then test it at home before you rely on it away.

Q: How do you record several nights in a row?

Charge fully before you start. Take the sensor off each morning. That ends the recording. If you leave it on, the device keeps recording your day and fills the memory. Sync as soon as you're back. When the memory is full, the device has no room for new nights. Check your manual for whether it stops or overwrites the oldest.

Q: What should you watch on a trip?

Altitude. Everyone's oxygen reads lower up high, so a mountain night isn't comparable to a night at home. See blood oxygen at altitude or try the altitude calculator. The same goes for a night on a plane. Notes. After several nights you won't remember which was which. Write down where you slept and what you had to drink.

Practical tips for wearing a Wellue Checkme O2 Max, recording several nights between syncs, and keeping those nights clean and comparable.

PulseOxTracker Team7 October 2026

The Checkme O2 Max has the longest battery life of Wellue's three overnight oximeters. It's a wrist unit with a finger sensor on a short cable. Here's how to use it across several nights.

What's the long battery good for?

Trips. Record several nights away without your charger or phone.
Skipping the morning sync. Useful if you don't want your phone by the bed.

How many nights you get depends on your model and how much the vibration goes off. Check the manual, then test it at home before you rely on it away.

How do you record several nights in a row?

Charge fully before you start.
Take the sensor off each morning. That ends the recording. If you leave it on, the device keeps recording your day and fills the memory.
Sync as soon as you're back. When the memory is full, the device has no room for new nights. Check your manual for whether it stops or overwrites the oldest.

How should you wear it?

Strap snug on the wrist so the unit doesn't slide and tug the cable.
Seat the finger sensor where Wellue's instructions show.
Run the cable along the back of your hand and leave a little slack.
Use the same hand and finger every night.

The SleepU wears the same way, and the SleepU tips have more on the cable.

If you get holes in the chart, the causes are the same as for the ring. See why your O2Ring data has gaps.

What should you watch on a trip?

Altitude. Everyone's oxygen reads lower up high, so a mountain night isn't comparable to a night at home. See blood oxygen at altitude or try the altitude calculator. The same goes for a night on a plane.
Notes. After several nights you won't remember which was which. Write down where you slept and what you had to drink.

Should you use the vibration?

It can buzz when your reading drops below a level you set. It's a nudge, not a safety monitor, so don't rely on it to wake you. It also changes the night you're recording. More in should you turn on the vibration alert.

It isn't a sleep study. If you snore loudly, someone has heard you stop breathing or gasp, or you're exhausted during the day, see a doctor.

When you're home, PulseOxTracker can connect over Bluetooth from Chrome or Edge and download every night on the device in one go. Then you can tag the trip nights and compare them with your nights at home.

Not a medical device. Does not diagnose, treat or prevent any condition. Discuss results and changes with a clinician.