Battery capacity
The capacity of the battery installed in the device (see "Power").
Theoretically, a higher battery capacity allows you to work longer on one charge. At the same time, the actual battery life will also depend on the power consumption of the device, and it is determined by a number of technical specs. Therefore, it is better to evaluate battery life not by battery capacity, but by directly claimed operating time (see below). It makes sense to use this parameter if the operating time is not specified; at the same time, it makes sense to make conclusions only if devices similar in specs differ in capacity — for example, 60 and 110 mAh.
USB charging port
The type of connector used to charge the built-in battery of Bluetooth headsets, more precisely, to connect an external charger. The role of such a device can be played by a network or car adapter, a power bank, or even a USB port on a PC or laptop (if you have the appropriate cable).
— microUSB. A smaller version of the USB connector designed for portable devices. It appeared quite a long time ago, but it does not lose popularity nowadays, despite the active implementation of the USB-C port.
— USB-C. A miniature USB connector, positioned, among other things, as a potential successor to microUSB. Unlike its predecessor, it has a double-sided design, thanks to which the plug can be inserted into the socket in either direction. It is still relatively rare, but the situation is likely to change in the coming years.
