Nitecore Limitless Power 18650 Extension Battery Case~ used for NU40, NU43, and NU50 Headlamps

NITECORE 18650 Extension Battery Case At-A-Glance Connects directly to headlamp Can charge a headlamp's built-in battery while the headlamp is on Lightweight and well-balanced design Four red flashing lights can alert others in your surroundings Power indicators to let you know when it's time to charge Included in the Box Nitecore 18650 Extension Battery Case Cable Clip (Battery sold separately) Power Extension for the NU40, NU43, and NU50 Headlamps The Nitecore Extension Battery Case is designed to extend the battery runtime of the NU40, NU43, and NU50 headlamps. When the headlamp is on, it will first be powered by the battery case, followed by the built-in battery of the headlamp allowing it to maximize its runtime. Lightweight and Comfortable Weighing only 2.2 ounces and directly attached to the headlamp band on the back, it provides a balanced weight distribution to the user for a comfortable and secure wearing experience. User-Friendly The Extension Battery Case is compatible with high-capacity 18650 rechargeable batteries, excluding flat-top batteries. Equipped with an intelligent charging function, connect a USB cable to a USB-C adapter to begin charging the battery when not in use. For added safety, it features four red flashing lights to act as a signal light at night. Short press the Power Button for the power indicators to illuminate your remaining battery power. TECHNICAL SPECIFICATIONS Input 5V ~ 2A Output 5V ~ 2A Battery Option 18650 Li-ion Battery (Flat Top Excluded) Dimensions L-4.17"xW-1.57"xH-1.38" Weight 65g/2.29 oz