For improved postural alignment and the ability to rotate a child's pelvis into a more desired position, the Mygo Stander has two derotational belts. Specific for either Supine use or Prone use, the derotational belts actually have two parts. The inner part wraps around and holds onto the child's pelvis. The outer part attaches to the frame and allows for gentle and secure rotation of the child's pelvis. This is especially helpful for those wiggle worm kids who end up turning themselves around and out of alignment in other systems.