Molded composite foam rollers are perfect for positioning balance postural and muscle re-education spinal stabilization body awareness and coordination and ranging and strengthening activities. * Round rollers offer progressive exercise sequences - user can graduate from an easier (smaller diameter) to a more difficult (larger diameter) roller. * Half round roller is a great tool for ankle stretching and knee rehabilitation. * Diameter refers to the width of the half-round profile. * The molded rollers are strong enough to be used by large adults and active children. * This line of rollers is available in black. The molded composite foam rollers are more firm than the polyethylene roller and are rugged. * Dimensions: 6 x 6 x 18 . * Weight: 2.0 lbs