The wheel roller is an excellent prop that can improve your yoga level, relieve back pain & body stress. It fits the curve of the back with its ergonomic design and is suitable for stretching the back. It is specifically designed to open the chest, relax the back muscles, align the spine, improve flexibility and balance. Three sizes to target different muscle groups and training needs. The 12” yoga roller wheel fits best for the average size adult, best for deeper poses, backbends, and assists you with both beginner and advanced asanas. The 10” wheel is for a medium pressure massage and stretch for back and hips. The 6” wheel is best for a deep focused tissue massage in the neck, back and legs. Made of premium quality ABS and extra thick TPE foam, eco-friendly, odorless, skin-friendly, durable, PVC free, safe and comfortable.