Please check in the comments as some colors may be out of stock. This is a name tag service, but of course, you can choose to have it without one. Made of 100% cotton, safe for babies. Knitted with cotton made in Japan. It's smooth and can be worn in all seasons. Please hand wash for care. M: Flat length approx. 15.5cm, width approx. 21cm, head circumference approx. 43cm. Head circumference is the length of the hat's head circumference when not stretched. Since it actually stretches, a hat that is the same length as the head circumference or about 1cm smaller is just right. Individual differences are large, so if possible, it would be helpful if you could tell me your child's age, head circumference, and the length from the crown to the top of the ear (the depth when worn). We are happy to discuss sizes, so feel free to comment. #acornhat #handmadehat