Scala, a long-established American hat maker, approximately 56 cm inner circumference. This hat has a fabric feel that seems suitable for fall, winter, and spring. Photos 14 and 15 were taken outdoors in the shade. No adjustment function. If it's too big, please use commercially available size adjustment materials or sew additional sweatbands. You can reduce the size by about 1 to 1.5 cm. Color: Green