Mainframe, MainFrame is a variable thickness pattern of grooves, channels, and cavities carefully milled into the backside of the Iron face that maximizes flex at impact.

Progressive Grooves, The 4i–7i feature wide grooves, ideal for longer shots in all conditions. The 8i–AW have deeper, closer set grooves which cut through grass and debris to enhance spin on approach shots. Laser milling between each groove, on every loft, enhances friction in all conditions.

Tour V.T. Sole, Tour V.T. Sole takes turf interaction to a whole new level of detail with a proprietary combination of sole widths, bounce angles, and notches that encourages a smooth glide through fairway, rough and sand to strike the ball solidly without losing speed.​