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The 21700 Intelligent Battery System is an innovative power solution which consists of the NITECORE 21700 i Series Battery, the ML21 Magnetic Light, and the MPB21 Magnetic Power Bank. Designed to offer a consistent power source and to minimize the burden in the outdoor activities, it can easily provide the necessary light source and transfer power between different devices on the go.

21700 i Series Battery

As a patent product developed by NITECORE (Patent No. ZL201820118916.0, US Patent Pending), the 21700 i Series Battery is a proprietary 21700 rechargeable Li-ion battery featuring dual way output with positive and negative polarities at both ends and a high energy density. It enables a highly efficient output by minimizing the loss of power due to internal resistance. A 21700 i Series Battery has an energy density of up to 240mWh/g, 11% higher than 18650 batteries.

The dual polarities of the 21700 i Series Battery at both ends have broken the convention of linking the head and the tail of the flashlight in order to minimize its size and weight. The internal resistance is therefore greatly reduced to offer a direct energy conversion to power the device. Thanks to the groundbreaking technology and techniques, this can bring more possibilities to our flashlight design, most notably the NITECORE i4000R Future Oriented 21700 Intelligent Tactical Flashlight. The 21700 i Series Battery is compatible with conventional chargers including NITECORE UMS2, UMS4, UI1, UI2 and more, besides other accessories in the 21700 Intelligent Battery System. It can also power conventional 21700 flashlights and other compatible devices.

ML21 High CRI Magnetic Light Module

With a max output of 80 lumens, it is perfect for either handheld or tail stand to be used in short-distance illumination such as reading, camping or emergency. 

Attach the ML21 to the end marked with (+) of the i Series Battery to activate the light. Detach to deactivate it.

MPB21 Magnetic Power Bank Module

Combined with a 21700 i Series Battery, it aims to provide a consistent power supply in the outdoor environment. After attaching the MPB21 to the end marked with (+) of the i Series Battery, use the USB cable to connect a USB device to the input/output port to begin the charging process.