Product size: 222*207*58mm.Powered by USB or battery: The USB rechargeable fan can be charged via your PC, a portable charger, or a car charger. With its built-in 2000 mAh battery, it can run for up to 6 hours on a full charge (a USB charging cable is included).Safety against strong winds: With 48 air outlets and 60 double turbo fan blades, this portable neck fan can quickly cool you down. The bladeless neck fan is safe for children and the elderly. For those with long hair, it's a godsend. You don't have to worry about damaging your hair. A fan around your neck will keep you cool on hot days.Three adjustable speeds: This neck fan has three speed options: low, medium, and high. With a single button, you can switch between three different fan speeds, making this neck fan suitable for all ages. Press and hold the button (approximately 1.5 seconds) at any speed to turn the fan off. The three adjustable speeds provide you with more choices for different temperature environments.Portable and compact: This hands-free neck fan is designed to fit over a helmet, allowing you to enjoy a cool breeze hands-free. Lightweight and portable, you can take it anywhere. It's a great companion for the gym, climbing, camping, the office, and more, especially in hot weather.Noise reduction: The portable personal neck fan produces low noise during operation, which will not disturb you, providing a comfortable and quiet experience.