These foam rollers are made with high density foam for superior support, strength, and ultimate stretching. Each foam roller is constructed to provide a deep tissue massage which can help alleviate pain, stiffness, and muscle soreness. Extra firm foam rollers allow more pressure to be applied to ease tightness and increase the flexibility and range of motion of your muscles and joints. The foam roller can be easily repositioned to target specific muscles and to assist from one routine to the next. Its design also helps assist when rehabilitating the upper and lower back, calves, hamstrings, glutes, and more.