This Adjustable Head Support is designed to remain cool in order to prevent pressure sores and adjusts in width to fit any body anatomy. Head support adjusts easily to prevent lateral head movement. Water-based gel packs relieve pressure on vulnerable ears. Can be used for all high-back wheelchairs, geri-chairs, and recliners. Low-Shear II wipe-clean outer cover reduces skin damaging friction. *Note: Model number 503099 serves as a replacement gel pack for both Heel Float and Adjustable Head Positioner.