This cover is designed to gently fit around the head. The material is water-repellent twill fabric (35% cotton, 65% polyester). While it quickly repels water, it also absorbs vapor such as sweat, dries easily, and is wrinkle-resistant, making it an easy-to-handle material. Because it's for your precious child, we've prioritized a balance of functionality and gentleness. ・Dark colors may fade during washing. We recommend washing separately with a neutral detergent.