Head circumference: 40-42cm I bought this hat when my baby was about 3 months old. We used it a lot. It was easy to put on when it was chilly, and the material was easy to handle. I was very grateful because it was hard to find hats for 3-month-olds. This is a used item, so I would like to sell it to someone who understands. I also welcome bulk purchase requests ╰(*´︶`*)╯♡ ＊Free shipping!! ＊Instant purchase is welcome, and silent purchases late at night are OK ◎ ＊First come, first served (╹◡╹) ＊Bulk purchases are welcome, with discounts available!! → Please feel free to contact me ^_^ ・Please understand that this item is stored at home and will be shipped in simple packaging. (´・ω・`) ・Please check the actual photos for the condition of the product♪ ※To keep the price as low as possible, we may remove the item from its box for shipping due to shipping costs. ※We may also compress the item. Thank you for your understanding.