The GRID foam roller is designed with proprietary Distrodensity zones. This three dimensional surface has a variety of widths to replicate the feeling of a massage therapist’s hands.Three-dimensional surface allows tissue to aerate while you roll promoting the flow of blood and oxygen—the nutrients needed to repair musclesHard hollow core hand-wrapped in EVA foam makes it firmer than traditional foam rollersEnvironmental design uses less foam than traditional foam rollersCompact and travel-friendlyBacked by a one-year warrantyWeight tested to support up to 500 lbs/225 kg static load