Unique ribbed shape design provides a deeper massage than your typical smooth surface rollers. Extra Firm surface provides a firmer surface than the Original Density models. Great foam roller for especially dense muscle tissue that does not respond to your average foam rollers. The Tri-Ribbed Foam Roller is a great foam roller to Alleviate Back Pain & other types of Muscular Pain. Is composition is 100% Raw Material & EVA Foam; Eco-certified EVA Foam that’s SGS passed. Used for Pilates, Yoga & Fitness Clinics.