Oneplus Nord Buds True Wireless in Ear Earbuds with Mic, 12.4mm Titanium Drivers, Playback: Up to 30hr case, 4-Mic Design + Al Noise Cancellation, IP55 Rating, Fast Charging (Black Slate)

Highlights:
• Almost New Condition
• It's Working Condition is as good as new one
• Perfectly Working
• Worth ₹3,500
Features:
• With Mic: Yes
• 12.4 mm dynamic drivers
• Upto 15 to 20 hrs of non-stop music on a single charge with Case.
• Al Noise Cancellation
• Fast Charging
• OnePlus Fast Pair is only supported on OnePlus 6 series devices and up running Android 11 and up. To ensure the normal use of your earbuds, update your Wireless Earphones (OOS 12 or later), OnePlus Buds (OOS 11 or earlier), or HeyMelody (non-OnePlus devices) app to the latest version using your local app store.

Note: to be on safer side, I mentioned the battery backup as low as possible, but it can give more backup than that,
And what u see on Google or What battery backup company claim, is measured in 50-60% Volume only.