This is a detachable collar that I purchased at a used clothing store. It's cream and brown lace knit, and it's very cute whether you wear it flat by loosening the strings, or with the strings tied to gather the collar and give it a slightly three-dimensional, frilly look. It's adorable with sweatshirts, of course, but also with knitwear, coats, and even T-shirts in the summer! The material is cotton linen-like, and it's very cute because it changes its expression depending on how it's gathered. Highly recommended. Regarding the size: The width is about 17cm, and the longest part in the front is 25cm. This detachable collar can instantly transform your usual outfit, and I'm offering it at a low price, so I hope you'll consider it! Please feel free to comment if you have any questions!