This yoga massage ball will help you relieve your stress. High density massage ball. Use your own body weight and gravity to help relieve muscle knots and tension. This item is made of qualified silicone and has a 2.5” diameter measurement. Popular with athletes and fitness enthusiasts, lacrosse balls have the right hardness for self-myofascial release (SMR) and can be used to activate trigger points in muscles. Two lacrosse balls joined together make blood circulation better and faster.Perfect size to target trigger point areas of the feet, hands, arms and legs to ease your sore spots.Portable, durable and easy to use.