Everything Yoga Cover for Round Yoga Bolster For years, our customers have been asking if they can purchase just the bolster covers, and now you can! These cotton round yoga bolster covers are the exact same covers that are on our standard round yoga bolsters. Each cover is 100% cotton, has handles on both ends, and features a full-length zipper so the cover can be easily replaced. Purchasing a new bolster cover is a great way to re-energize your yoga bolster, add to its life-span, or change your color themes.