Meet the essential cotton sweater. Lightweight and sturdy enough to wear on its own, this sweater is perfect for transitional fall days when you can't commit to fleece. The shaker sweater is made with 100% cotton seed stitch. Seed stitch gets its name from the texture of the knitted fabric Ñ the little purl bumps look like scattered seeds. It consists of single knits and purls that alternate horizontally and vertically.