Thickness gauges with built-in battery

Built-in battery

— in this case, it is meant to be powered by its own battery, which is not related to standard sizes; it can be both non-removable and removable. Anyway, such a power source cannot be quickly removed and replaced with a fresh one, unlike replaceable batteries — you need to put the battery on charge, and this takes time and external power. On the other hand, the built-in battery comes with the device from the start, and the user does not need to buy it separately or constantly spend money on disposable batteries. In addition, built-in batteries often outperform replacement batteries in terms of capacity, while being more compact at the same time.