RSi1 provides the ultimate performance on shots hit away from the center of the clubface, the irons are infused with all of the speed and distance Tour Pros and amateurs alike have come to demand from TaylorMade. RSi1 feature an improved Speed Pocket with ThruSlot Technology in the 3-7 irons which increase launch angle and ball speed on all shots. The Speed Pocket gives golfers ball speed protection on shots below the center of the face, further improving performance on mis-hits. Combine all of that with our thinnest face, deep undercut and Inverted Cone Technology and RSi1 gives golfers maximum face speed for maximum consistent distance. Our engineers have also improved sound and feel via advanced construction & multiple sound management systems. And the new Reax 90 steel shaft from True Temper helps to optimize ball flight for ultimate distance and performance.