Mizuno conducted countless hours of player testing with players from the PGA Tour, Nationwide Tour, and European Tour. The Mizuno MP-68 Irons competed in blind tests against multiple prototype iron designs as well as Tour-proven Mizuno irons from the past, such as the MP-33, considered by many to be the standard of muscleback design. The MP-68 irons also have a Tour Confirmed sole shape that ensures the appropriate amount of turf interaction for pure ball striking. Mizuno’s Grain Flow Forging process ensures that the MP-68s provide the feel and ball control that better players demand.

Mizuno MP-68's scalloped muscle back and shorter hosel allow a lower, more centered COG location for a penetrating, workable ball flight. Neutral bias allows shots to be shaped both left and right. The New Mizuno MP-68 Irons with 3D muscle technology are the next generation of muscleback irons. The innovative 3D muscle is the result of extensive computer optimization to deliver the ideal COG location that is lower and more face centered providing a penetrating and workable ball flight for complete shot control.

In addition, the sole of the MP-68 Irons features a rolled leading edge and trailing edge for better turf interaction and a flattened mid-sole enables more precise ball striking. A shorter hosel has created a centre of gravity that contributes to a penetrating, workable ball flight that the neutral bias allows you to work left or right.