Strauss Grid Foam Roller, 45 CM, (Purple) Hard, hollow core hand-wrapped in EVA foam makes it firmer than traditional foam rollers Three-dimensional surface allows tissue to aerate while you roll, promoting the flow of blood and oxygen—the nutrients needed to repair muscles Waterproof, anti-slip, non-toxic, tasteless, odourless, the most popular Pilates yoga trainers, can also do children's sporting goods, swim rod The textured surface gives you extra grip to prevent sliding when using on the floor. Environmental design uses less foam than traditional foam rollers Unique Distrodensity Zone Design Allows For Targeted Massage.