This is a Slyly cap. I bought it at the Hiroshima baseball stadium a few years ago. Measurements are approximate, as I am not a professional, but: Cap circumference: approximately 63 cm Adjuster: 6 cm Please use these as a size guide. My child tried it on, and I bought it, but it has been stored ever since. Please understand that this item has been stored at a private residence. Please refrain from purchasing if you are overly concerned about the condition. The cap's brim is stiff, so I plan to ship it without crushing it as much as possible. Therefore, the shipping cost will be a bit high. I am open to discussions, but please refrain from significant price reductions. #Carp #Slyly #Baseball #Cap