ForPro Premium Jumbo Half-Round Massage Bolster is made from high-density foam and vinyl. It is designed to relieve strain from lower back during massage therapy and add comfort during yoga and stretching. The semi-round pillow is flat on one side to prevent rolling and conforms to the body’s natural curves and provides support for the vertebrae and back. The bolster can be placed under the knees during face up massages, under the ankles when face down, and can also be used to support the neck. It is oil and stain-resistant.