Dragonfly 4" Cork and Recycled EVA Foam Yoga Block The Dragonfly Eco Cork yoga block incorporates recycled EVA foam into the natural anti-microbial cork material. The increased weight helps provide the stability needed for optimal alignment, increased strength and assistance in reaching deeper poses. You can ground your hand in standing poses, space your hands in peacock poses or support your hips in bridge poses. Made from natural and recycled materials, the Eco Cork block is perfect combination of uncompromising performance utilizing eco-friendly materials.