The Titleist 731PM irons were a limited edition release iron set inspired by Phil Mickelson, who collaborated on their design. The set is a blended set of cavity back long irons, muscle cavity mid irons and muscleback short irons. The irons shape was designed with the preferences of "Lefty" in mind with a rounded toe, strong bounce and stronger lofts to match Phil's iron specs. The clubs are cast 431 stainless steel and also feature a traditional "V" groove design. Buy the Limited Edition Titleist 731PM irons from 2nd Swing and take advantage of our trade in program to get the best values in the industry for your used clubs.