I upcycled a vintage kids' dress and sweatshirt to create a detachable collar for adults. This detachable collar is new. It has a simple round collar shape, making it easy to pair with T-shirts, sweatshirts, sweaters, and turtlenecks. It can be easily removed with snap buttons. It's reversible, featuring a black, 100% wool check pattern and the reverse side of the sweatshirt material. I actually wear this detachable collar myself, and when I'm rushing around in the morning and feel like something's missing, it adds a nice accent to my outfit. By wearing the collar, my neck feels warm, and I've discovered that it's perfect for the changing seasons, even if you don't need a scarf or neck warmer. It's compact, so it doesn't take up much space when removed and put in your bag. Also, it's not bulky even when you wear an outer layer. Size (flat measurement) Neck circumference (inside): Approximately 42 cm - For washing, please hand wash or use the delicate cycle in a washing machine with a laundry net. - This is a handmade item, so please understand and accept any imperfections such as uneven stitching, double stitching, or re-stitching before purchasing. Thank you for looking.