This is a very popular swaddle on Rakuten Ichiba. The size is M, and it seems to be suitable for babies aged 3-6 months. I purchased it about a year ago and used it for about 1-2 months. My child's nighttime crying became severe around 3 months old, and I wasn't getting enough sleep, but this swaddle helped them sleep well, and I was very grateful. The zipper area is slightly worn, but there are no noticeable stains overall (photos 5 and 6). Thank you.