External battery (power bank) – PURIDEA S12. It allows you to charge devices without access to a permanent power source. Available in several colors. The battery capacity allows you to fully charge a standard smartphone (a standard smartphone has a battery of approx. 2000-2500 mAh). Compact size means that the charger can be taken with you on a journey; small size ensures comfort of use. Solid housing is durable and resistant to damage. Specification: Capacity: 5,000 mAh / 3.7V (18.5Wh) Input (Micro USB): 5V-2A Output (USB): 5V-2A NOTE! Nominal capacity expressed in mAh (milliampere hours) means the sum of all cells that were used in the power bank. The cells used have a voltage of 3.6 – 3.7V, while the standard USB port – 5V, so voltage conversion is necessary, which in turn translates into real capacity. After conversion, it is usually around 65-67% of the original value. This means that for a power bank with a capacity of 12,000 mAh, in fact about 8,000 mAh is available.