Callaway Golf Men's XR OS Combo Set Long with our industry-leading Face cup: we've taken our cup 360 technology that's redefined ball speed in the category, and helped US become the #1 iron in golf.And we've made it even faster Easier to hit XR os irons are easy to launch with a center of Gravity that's lower and further back. It's easy for you to get a ball flight that leads to more distance More forgiving: the soles are wider to give you more forgiveness, and it's easier to get more distance out of every impact location. You'll feel confident over the ball, and you have the technology to hit good shots more consistently Progressive lengths and lofts to HELP you hit the ball farther, we've included the progressive lengths and lofts through the set for longer distance off each club