Manduka Recycled Foam Yoga Block Mandukas Recycled Foam Yoga Block is made up of over 50% recycled EVA foam, this lightweight yoga block provides unbeatable comfort, style and support. High-density cushion for unparalleled experience, joint protection, and versatility on any surface (carpet, cement, hardwood floors). Radius edges for comfort and beauty. Soft, comfortable grip that is also slip-resistant.