St. Patrick’s Day Decorative Pillow Covers for 18” Pillows. Add some luck of the Irish to your Decor. Adorable pillow covers. You get a set of 4 as shown in pictures and video. These are machine washable and can be used year after year. Made of polyester linen blend. Pattern on front only, no print on back. hidden zip closure to fill pillow with pillow insert or batting material. See pictures for measurements. Suitable for sofa, chair, bed, home and office. ***NOTE: pillow covers only, pillows are not included.