Case battery capacity
The capacity of the battery installed in the case (case) for headphones.
This parameter is relevant only for true wireless models (see "Cable type"). Recall that these headphones are charged from a case, which is usually equipped with its own battery and actually works in standalone power bank mode. Knowing the capacity of the battery in the case and in the headphones, you can estimate how many charges of the “ears” will last for one charge of the case. However, it should be taken into account that in the process of charging the headphones, part of the energy is inevitably spent on third-party losses, and the effective capacity of the case turns out to be somewhere 1.6 times less than the claimed one. This is the starting point for calculations: for example, a 300 mAh case will actually be able to transfer 300 / 1.6 = 187 mAh of energy to the headphones, and 30 mAh “ears” from such a battery can be fully charged about 6 times (187 / 30 ≈ 6).
Charging time
The time required to fully charge the battery in properly powered headphones (see above).
In this case, we mean the battery charging time from 0 to 100% when using a standard charger (or a third-party charger with identical characteristics). Accordingly, in fact, this indicator may differ from the claimed one, depending on the specifics of the situation. However, in general, it is quite possible to evaluate different models and compare them with each other: headphones with a shorter claimed charging time will in fact charge faster (ceteris paribus).
Also note that an increase in battery capacity (and headphone battery life) inevitably implies an increase in charging time. To compensate for this moment, special fast charging technologies can be used — however, they affect the cost and require the use of specialized charger.
Touch control
This feature means that the controls in the headphones are not traditional buttons that you need to press, but sensors that are triggered by touch.
Touch control is somewhat more expensive than push-button control, but it has a number of advantages over it. Firstly, it gives the headphones a neat and technological appearance, with a minimum of protruding parts. Secondly, due to the absence of moving parts, the sensors are more reliable and compact. Thirdly, it is purely physically more convenient to use them, especially with the small size of the headphones. These moments are especially relevant for the "ears" of the true wireless format (see "Type of cable"), so it is in them that touch control is most often found. However, there are exceptions to this rule. Also note that the difference in price between buttons and sensors is often almost imperceptible compared to the cost of headphones in general.