Product Description:1.The size of the hat can be adjusted. It is suitable for adults and children.2.It is driven by solar energy without other batteries or power; as long as there is sufficient sunlight, the fan will automatically start. You can also remove this small fan and install it in other places where you need it.3.Indoors Or a small fan in a dark place will automatically stop running; the solar fan cap is novel, fashionable, peculiar, practical, and energy-saving and environmentally friendly!4.The new model is upgraded to the market, with good sun-shading and sun-proof effects, and there is a mini fan at the front of the brim.5.The cotton fabric and hard-lined brim are ventilated, durable and well-made.Product Details:Battery board parameters: 2V80mAPacking method: opp bagProduct material: cottonProduct size: 30*20*12cm/11.81x7.87x4.72in