On new XXIO Prime Irons, a soft/rigid structure combines a flex zone in the lower body with a rigid zone in the rear of the body for enhanced energy transfer in the lower half of the face.
SUPER-TIX® TITANIUM FACES
Each Iron face is made of Super-TIX®-51AF Titanium, an incredibly strong yet lightweight alloy for thinner faces that increase face flex and ball speed on all your shots.
Dynamic variable face thickness and a high-density tungsten-nickel weight in the toe (of 5i–7i) optimize speed, stability, and launch for each loft. A lower Center of Gravity for long Irons creates more carry; a higher one for short Irons emphasizes control.