THE MB1 Massage Ball is composed of foam and is specifically designed to replicate the feeling of a massage therapist's hands. Featuring a patented, layered construction made up of different densities, the massage ball works to break up adhesions and stimulate blood flow to ease joint and muscle pain more effectively and restore movement more quickly. The unique EVA foam surface is very dense, yet still compresses to "grip" the tissue, encouraging blood and oxygen flow to keep muscles and fascia healthy. The MB1 Massage Ball is machine washable, lightweight, and slip resistant. 1-year manufacturer's warranty. TriggerPoint empowers people of all lifestyles to move and feel better. TriggerPoint designs and develops innovative massage therapy tools that mimic the touch of a therapist's hands - making their foam rollers, hand rollers, massage sticks and balls ideal for individuals of all ages, sizes, and athletic ability.