Pretty vintage soft cotton flannel fabric, great for a flannel shirt, lounge pants etc.. This is a 9 1/2 yard length of 45" wide fabric, a full bolt or nearly so.
It's never been laundered, and is dirty, stored in a trunk in a barn for many years. This has soil / yellowing to the selvage, fold lines and other areas along the length, and has uneven color from fading or soil. There's a lot of fabric to work with here, though!