Do aftermarket batteries have the same capability and longevity as their branded counterparts

In a simple word – yes – but what aftermarket batteries bring to customers (in addition to long life performance and similar technical ratings and components) is affordability.

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As a customer of batteries what is mission critical is that your device (whether it is a laptop, PDA, two-way radio, power tool, or flashlight) works on battery power. Your device does not care whether you have a big brand battery name on it or a generic aftermarket battery! What is important to your device is that your voltage, capacity, chemistry, and all the internal and external components meet the specific design needs of your device.