Cars hat. I bought it at Costco, but it's already too small, as I never used it. I removed the tags. The sunshade at the back of the neck is not removable, but it can be rolled up and secured. Perfect for playing in the park or going for a walk. Inner circumference: approximately 50 cm Although it's unused, it has been stored at home. I will ship it as compactly as possible. Thank you for your understanding.