This is a monochrome flannel shirt from UNIQLO. It's a style that was sold in the mid to late 2000s, so it's no longer available. The thick fabric makes it suitable for fall, winter, and spring. The spare buttons are still attached, and I think it's in good condition. It would be great for Y2K or oversized styles! It looks white from a distance, but it's an off-white color, which is my personal favorite check pattern.