Fairfield-Poly-Fil Micro Beads. Micro Beads are made of 100% mini virgin expanded polystyrene beads. These beads are used in some of the most popular decorative pillows on the market today. Use this filler for stuffed animals, pillows, pet beds and craft projects. The advantage of using micro beads is the softer, smoother feel to anything you fill with them. This package contains 20oz: approximately 1/2 cubic foot. Made in USA.