Utilizes Yonex's Impact Speed technology for enhanced frame response. The "iS" in RDiS stands for Impact Speed-a snap-back action which stores energy on impact, then releases it with tremendous power and speed. Yonex also utilizes a new graphite construction known as Cup-Stack Carbon Nanotube in its RDiS racquets which helps the frame flex, yet provide quick repulsion for power and a solid feel.