MuscleGlide muscle therapy tools are the most versatile and effective massage tools available. The 4-wheel unit can be used to roll over when placed on a chair, table, floor or against a wall like a foam roller; or used manually on yourself or a partner to massage all parts of the body. The special wheel shape and spacing allows the MuscleGlide to massage out stiff muscles and break up muscle knots without mashing the muscle like other products. Easy to use and feels great!