The Nitecore NU40 is another new addition to the NU series. The NU40 is powered by a built-in 18650 battery with a capacity of 2600 mAh. An improved charging circuit allows the battery to be fully charged via the USB-C charging port in just 1.5 hours. Furthermore, the Nitecore NU40 can be used while charging. There will soon be compatible accessories available that can be attached to the headband. The housing is made of metal and polycarbonate, resulting in a lightweight design – the NU40 is currently one of the lightest headlamps with a 18650 battery. The 32 mm wide headband ensures a comfortable fit and optimal weight distribution. The built-in optical sensor instantly reduces brightness as soon as it detects an obstacle in front of it, preventing overheating from accidental activation.