A mysterious new Apple battery unit has just passed inspection by Korean authorities, and pundits are speculating about the products it could feasibly appear in. The most likely is the Apple Watch Series 6, and if this is correct, Apple's wearable is about to get a boost in battery capacity.

The new unit, which has the model number A2327, is previously unknown and has a capacity of 303.8mAh, or 1.17Wh. The Twitter account @yabhishekhd was the first to reveal the unit's specs.

The battery may be used for an upcoming AirPods case, but in appearance it looks more like a battery from an Apple Watch, writes 9to5Mac. The next Apple Watch is rumoured to have a slightly larger battery to make it more suitable for sleep tracking.

The latest model of the Apple Watch, the Series 5, has a 296mAh battery. The Series 4 had a 291mAh battery, while the Series 3 had 279mAh.

Catch up on all the latest rumours in our Apple Watch Series 6 launch news roundup.

This article originally appeared on Macworld Sweden. Translation by David Price.