GolgiStim Large Trigger Point Massage Ball - Hard Rubber Therapy Ball for Myofascial Massage - Deep Tissue Massager for Myofascial Release and Pressure Point Recovery (Red (Medium))Simple Design and Use: Simply lean on the massage ball and use your own body weight and gravity to relieve muscle knots and tension. See video and images in the listing for more specific exercises. Effective Deep Tissue Treatment: These 4. 75 Inch Trigger Point therapy balls help for immediate and long term results. The deep grooves reach far into inner muscles & joints to iron out knots, relieve tightness, & and may improve circulation over time.