The Nitecore F21i turns your iSeries battery such as NL21500HPi into a minimalist battery charger and power bank. The F21i features a USB-C port that functions both as a battery charger when connected to a power adapter and as a power bank when connected to a device. The 3-dot blue indicator beneath the USB port flashes to indicate the charging progress. Supporting Quick Charge and Power Delivery (QC, PD) protocols, F21i delivers an incredible 18W of fast charging output. The F21i is a mini multi-functional battery charger and power bank as well as a must-have backup battery and accessory for any iSeries tactical flashlight.
The F21i is ultra-compact, durable and safe to use. It is about 2 inches long when stowed away and only 4 inches long when fully stretched. Its rigid battery cap is made from fire retardant polycarbonate. It also comes with the same comprehensive safeguards as the other Nitecore chargers: overcharge protection, overcurrent protection, over-discharge protection, short-circuit protection, thermal protection, and overvoltage protection. Always be prepared by pairing a F21i with a iSeries battery for emergency power.