3 Adjustable Brightness: LED headlamp contains 4 bulbs, you can press the power button switch to 3 brightness (50%, 75%, 100%), lowest brightness of LED beanie for about 6-8 hours, middle for 4 hours, the brightest gear 2 hours. the battery may be out of power at the the first time, it is mormal, please charge the light before your first using. Rechargeable: LED hat contains a rechargeable lithium battery and USB interface, hat light suit for computer, power banks, adapters, car chargers. The indicator of beanie light will turn red when charging and turn green after about 2 hours of charging, 2 hours to fully charge and last 8 hours of a battery life time. Size and Design: The size of unisex skull cap is 7.87 * 8.6 inches, head circumference is 22-25 inches, good comfort and convenience, suitable for most people, helps you resist the cold wind. In addition, the cap is detachable and can be washed by hands or machines. Remember to take off the light before washing. 2 in 1 LED Flashlight and Winter Hat: This fashionable beanie hats for men uses soft knitted wool, flexible to effectively isolate the cold winter air. keep warm and light during outdoor activities at night. A running hat to match different clothes in winter. Various Scene: This skull caps for men is waterproof, suitable for camping gifts, running lights for runners, fishing gifts for men, cycling, walking at night, walking the dog, running, jogging, camping, fishing, outdoor camping, snow trekking, skiing and can be an ideal Christmas birthday gift.