1. Easy to install and : if you have an LED knit beanie hat, just the broken light lamp with an LED light lamp; If your hats are without LED, you can cut the hats according to the shape of the light; Equipped with leather traps, you can sew the leather traps on your hat and install the light. This combination is suitable for anywhere you need work lighting while freeing your hands. 2. USB charging: the flashlights have a standard USB, which can be charged through any standard USB port; You can use a car charger, computer, socket, and portable power bank to charge. The indicator turns red when charging and green when fully charged, easy and convenient to use. 3. Suitable for hats, a complete combination for easy illumination in the dark. This LED lamp has 3 adjustable brightness levels, namely strong, medium, and weak light modes. You can choose the appropriate brightness to see clearly in the dark. 4. Simple to apply and clean: press the button in the middle of the LED light to adjust the brightness you need. For cleaning, gently twist the light lamp cap to remove the lamp on it, and then you can wash the beanie hat simply.