A powerful battery whenever you need it. Just 92 gramm but a staggering 10.400 mAh with 40 Wh and 3,6 Volt.
These are the numbers. You might also appreciate the silicone cap to cover this lithium ion battery's outlets and keep them unharmed from dust and water splashes. With two USB outlets you can charge to devices at the same time.
To charge BioLite Charge 40 itself, connect it via the micro USB cable (that's included in the package) to any other power source. The four LEDs inform you about its current charge status.