The USB rechargeable batteries maintain a steady voltage until the entire battery is drained.
Easy and convenient, it can be charged directly from anywhere with the Micro USB cable. Built-in light shows the charging process. The self-contained four-port cable allows you to charge all of them and resume use in no time.
Since these batteries cannot be charged with the normal battery charger, they must be charged with the cable provided. There is also no need to buy an extra battery charger to charge it.