NCAA Michigan State Spartans Mens Polar Fleece Sleepwear / Pajama Pants This is a high quality, officially licensed NCAA Michigan State Spartans product. Extremely high quality fabric: 100% polar fleece micro-polyester; Machine washable. Team logo printed allover the pants for a sporty look. We completely guarantee the quality of all of our products - if you are not happy you can return your item for a full refund.