UOOPOO Customized Standard Pillowcase Genius Nerd Brain Black and White Brain Throw Pillow 18 X 18 Square Cotton Linen Pillowcase Cover Cushion Dimensions: 18" x 18", standard size for your pillow. Burlap Cotton Linen Material, healthy and durable. Hidden Zipper at one side, available for the pillow fillin. Image print back or front, please see the photo shows. Not include the insert, just the pillow cover. Machine washable.