Trigger Points Grid Foam Roller features a unique 3-dimensional surface that does not prohibit bloodflow at the point of pressure. Practice Self-Myofascial Release Therapy with a Matrix of 3-D Distrodensity Zones that allow blood and oxygen to channel through and create elasticity in the muscle delivering a precision massage. Environmentally conscious, Trigger Points Grid Foam Roller has a hollow core and sturdy EVA foam construction that uses less foam than your ordinary foam roller and will not break down with normal day-to-day use. The durable, travel-friendly and environmentally conscious product is backed by a 1-year warranty. Low & Flat Distrodensity Zones Feels like the forearm or palm. High & Firm Distrodensity Zones Feels like fingertips. Medium & Tubular Distrodensity Zones Feels like the fingers and thumb. Great tool for stretching, promoting flexibility, alleviating muscle and soft tissue tightness and Myofascial Release. Soothes tight fascia while increasing blood flow and circulation to the soft tissues. Uses your own body weight to apply gentle sustained pressure on the soft tissues. Myofascial release results in softening and lengthening of the fascia, which has been shown to relieve various muscle and joint pains. Improves flexibility and range of motion.